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of osmotic pressures in plants and animals, chemo- be realised at possible concentrations; (5) that a theory taxis, the theory of ionisation and its application to
deduced for volatile solutes may be extended to other cases. the germicidal action of disinfectants, the permea
When other solutions and different membranes are bility of membranes and the influence of this on secre
employed, one or more of these conditions may fail, and tion, the velocity of reactions, catalysis, colloidal solu
the theoretical value be beyond the reach of experimental
attainment. Prof. Kahlenberg remarks that because a tions, and the bearing of physical chemistry, on serum
semi-permeable membrane does not exist, a theory which therapy, in which connection the work of Ehrlich,
postulates one cannot be maintained. We might construct Arrhenius, and Madsen is briefly reviewed. Alto
a parallel statement by saying that because a frictionless gether this book supplies a decided want, and can be
piston is not practically obtainable, in Carnot's engine and thoroughly recommended.
the science of reversible thermodynamics physicists and engineers have imagined a vain thing.
But I may point out that at least two perfect semi
permeable surfaces are probably known : (1) when a soluLETTERS TO THE EDITOR.
tion freezes to give the solid of the pure solvent, the solute
is compressed into a smaller volume of liquid solution; the [The Editor does not hold himself responsible for opinions
surface of the growing crystals is semi-permeable, expressed by his correspondents. Neither can he undertake
(2) When a volatile solvent evaporates from the solutior to return, or to correspond with the writers of, rejected of a non-volatile solute, the free surface of the liquid is manuscripts intended for this or any other part of NATURE. again a semi-permeable membrane. From these two facts No notice is taken of anonymous communications. ]
follows the validity of the thermodynamic relations between
the osmotic pressure on the one side and the freezing point Osmotic Pressure.
and vapour pressure on the other. This is important, for
it enables us to use measurements of freezing points or In the issue of Nature for May 3 (p. 19) appeared an
vapour pressures when it is not possible to realise the abstract of recent paper by Prof. Kahlenberg on experimental conditions necessary for a satisfactory deter“ Osmosis and Osmotic Pressure." In Prof. Kahlenberg's mination of the true osmotic pressure, paper, and also in the abstract, it is claimed that his ex
Osmotic pressure is a thermodynamic conception.
The periments invalidate van 't Hoff's theory of osmotic pres
pressures observed in practice may or may not represent sure, by which the concordance between the pressure of the same thing. We may define osmotic pressure as the gases and the osmotic pressure of dilute solutions was
excess of hydrostatic pressure it is necessary to exert on establisined. As the basis of that theory seems sometimes a solution in order that it may be in equilibrium with the to be misunderstood, may I be allowed to recall the prin- solvent through a perfect semi-permeable membrane. ciples on which it is founded ?
With this definition we may use the conception of osmotic In a paper published in the Zeitschrift für physikalische pressure as a basis for a Carnot's cycle and a thermoChemie for 1887, van 't Hoff showed that, from the well- dynamic theory of solutions. Prof. Kahlenberg writes that known experimental relation between the solubility of a gas opponents of van 't Hoff's idea have generally held that and the pressure, it followed by a simple application of the the so-called osmotic pressure is an ordinary hydrostatic second law of thermodynamics that the osmotic pressure pressure, brought about by the entrance of liquid into the of a dilute solution must possess the same value as the osmotic cell. It is delightful to find one point at least in ordinary pressure of a gas at the same concentration. The
which the supporters of van 't Hoff, and van 't Hoff him. solution must be so dilute that the dissolved systems, each self, are in complete agreement with his opponents. made up of a particle of solute as nucleus, and the portion In the abstract of Prof. Kahlenberg's of solvent which it influences, are beyond each others' appeared in Nature we are warned that, among the general spheres of action. The proof has been put in a modified ruin of physical theories which is to follow his experiform by Lord Rayleigh (NATURE, 1897), and Prof. Larmor ments, the hypothesis of ionic dissociation is involved. I has obtained the same result by using the fundamental confess that the warning leaves me unmoved. The idea conceptions of the inolecular theory as a basis, instead of
that the ions of electrolytic solutions are dissociated from the experimental solubility relations of a gas (Phil. Trans., each other during their movement (though possibly or A, 1897). In all these proofs no assumption is made as to probably combined with the solvent) is required by the the nature of osmotic pressure. It may be due to molecular electrical phenomena. The abnormally great osmotic impacts or to chemical affinity, or to some other undis- pressures of certain electrolytes dissolved in water indicovered cause. The strength (and weakness) of a thermo- cate some kind of dissociation, but cannot tell us whether dynamic proof lies in this very independence of assumptions or not that dissociation takes place so as to give rise to as to the mechanism by which the effects are produced. electrified systems. In simple salts such as potassium Prof. Kahlenberg and his followers seem to consider that chloride, which we know by their electrical properties to be the thermodynamic theory of solutions stands or falls with electrically dissociated, it is difficult to see how a second the hypothesis that the pressure is due to molecular bom- kind of simultaneous dissociation could occur. But that bardment.
non-electrical separation is sometimes found is indicated If the conditions assumed in the proofs are realised, the by some older experiments of Prof. Kahlenberg himself, whole authority of thermodynamics goes to support the who found that solutions of diphenylamine in methyl result. The importance of experiments on osmotic pressure, cyanide show abnormally low molecular weights, but are such as those of Prof. Pfeffer, Lord Berkeley and Mr. non-conductors of electricity. The theory of ionic disHartley, and Prof. Kahlenberg, lies in the question how sociation rests upon electrical evidence, and by such evidence far the assumptions made in the thermodynamic proofs can it must be tried.
W. C. D. WHETHAM. be realised experimentally. This is a much humbler rôle Trinity College, Cambridge, May 12. than that assigned to the experiments by Prof. Kahlenberg, who claims that the application of gas laws to solutions is based on the few observations of Pieffer and others CONSIDERABLE importance seems to be attached to by which those laws have been verified directly. Never
paper by Prof. Kahlenberg on Osmosis and theless, the experiments are of great interest. The gas Osmotic Pressures" (Jour. Phys. Chem., vol. x.). as is value for the osmotic pressures measured by Pfeffer shows evidenced by a separate summary published in NATURE that the conditions laid down in the thermodynamic theory (May 3, p. 19). In these circumstances it may not be out are realised in practice : (1) that for sugar solutions in water of place to point out that the conclusions Prof. Kahlenan approximately perfect semi-permeable membrane has berg deduces are not warranted. been obtained ; (2) that no selective action such as could be On p. 142 he says “indirect measurements of osmotic produced by a Maxwellian dæmon is in operation ; (3) that pressures. from
vapour tensions ... involves the the molecules of cane sugar in solution are the simple mole- assumption that the gas laws hold for solutions." This is cules indicated by the chemical formula, though they may contrary to fact. We have shown experimentally (ser or may not be combined with solvent molecules ; (4) that vol. lxxvii. Proc. Roy. Soc.) that aqueous solutions of cane a solution which is dilute in the thermodynamic sense can i sugar give the same osmotic pressure whether observed
directly or deduced indirectly from their vapour pressures, taken of the distribution of the charges producing the and the relation connecting the osmotic and vapour earth's field, the increase in the ionisation will produce puur is quite independent of the “ gas laws holding a local increase in the earth-air current; but by hypothesis bur olutions."
the conductivity of the air close to the earth is unaltered, Leaving out of consideration the experiments made so that the increase in the current must be accompanied tfore the solutions were stirred-for on Prof. Kahlen- by an increase in the potential gradient close to the surface. berg's own showing these are not good-his conclusion that This is, of course, produced by negative electricity flowing the g. laws do not hold for dilute solutions in pyridine from other parts of the earth. 15 based on four experiments. If one may take No. 59 The above, I imagine, is an exaggerated but otherwise p. 2011 is a type of these, it is easy to show that the trustworthy picture of the effect an ionising radiation from teicat is valueless.
outside would have on the earth's electric field. The conThe sugar solution used is o 125 grm. mol. per litre, ductivity produced by the rays in the upper atmosphere and a pressure of 98 cm. of mercury is reached, but the must be enormous compared with the effects close to the theoretical value is some 3 atmos. Yow on p. 184 the earth. Even if the rays were homogeneous, only a mere diuinetre of his gauge is given as 0.5 mm., and he says trace would remain after passing through a layer of air that at the end of three days 0.115 grm. sugar has come roughly equivalent in absorbing power to 76 cm. of mercury: through the membrane-this quantity represents 2.8 c.c. But it is far from probable that they are homogeneous, and ?* solution. 11 we assume that this volume of solution
anv want of homogeneity would exaggerate the effect. are through the membrane at a uniform rate, a simple Other factors conspire to this end : the presence of dust alıulation will show that the rate is equivalent to a fall near the earth loading the ions and the smaller rate of rer! 20 cm. per hour in the gauge. No wonder the
combination at low pressures; whilst the increase in the Itroretical pressure was never reached !
mobility of the ions at low pressures would just compensate BERKELEY.
for the feebler absorbing power of the upper atmosphere. Foxcombe, near Oxford.
E. G. J. HARTLEY. It will be observed that the effect on the earth's field
of an increase in the ionisation of the atmosphere depends Diurnal Variation of the Ionisation in Closed Vessels.
entirely on where that increase takes place. If the con
ductivity increases in a greater ratio close to the earth's is his letter on this subject published in NATURE of surface than it does further away, the result ought to be Var 3 (p. 81 Mr. G. C. Simpson is, I venture to think,
a fall in the potential gradient. Mr. Simpson rightly points under a misapprehension regarding the conditions which
out that such a relation between the potential gradient Crtermine the variations of the earth's electric field. His
and the leakage of electricity near the earth's surface has statement of the problem, which I have slightly abbreviated,
been shown to exist. From my point of view this indicates * 23 follows :-" It is usual to accept that there is a
that the bulk of the ionisation near the earth's surface is ragatire charge on the earth's surface, and the correspond- not caused by radiation from an external source. ing positive charge is a volume charge distributed in the
O. W. RICHARDSON. 3tmosphere. There is very little volume charge in the air
Trinity College, Cambridge, May 12. close to the earth's surface, so the relation between potential gradient and charge on the earth's surface is given by di dh= - 470, Hence it follows that with a given charge Defects in Ostrich Feathers in South Africa. on the earth's surface and the corresponding charge in the atmosphere above, the vertical distribution of the The domestication of the ostrich on a practical basis charge and the conducting state of the upper atmosphere was undertaken in Cape Colony about 1867, and since do not in the slightest affect the potential gradient within
then ostrich farming has become one of the most important i few mrtres of the earth's surface."
industries in the eastern province. The census of 1904 Ai this is very true, but it is equally true that with a gave 357,970' tame ostriches in the colony, while the exconstant charge on the earth's surface nothing whatever port of feathers reached 470,381 pounds, practically the il affect the potential gradient close to it. Since the whole of which came from tame birds; the estimated value [tential gradient is a constant multiple of the surface
of the feathers was 1,058,9881., giving about 31. 105. per density. it is absurd to consider the variation of the one bird of feather-producing age. During the forty years of whilse the other is kept constant. The only assumption domestication the instincts of the ostrich have apparently that ir seems safe to make about the state of the earth's undergone no change, though its habits are much altered. surture is that, owing to the relatively high conductivity The feathers cut from the tame bird are shorter, weaker, but the earth's crust, for purposes of atmospheric electricity
and not so fluffy as those taken from wild birds, but I may be treated as an equipotential surface. The charge probably these differences are to be correlated with the in any particular region will be determined by the dis- greater frequency of plucking, and not with any constitribution of electrification and ionisation in the atmosphere,
tutional change resulting from domestication. and will readjust itself almost instantaneously when any
Within recent years much concern has arisen from the harge takes place in the external conditions. It will not, prevalence of a defect in the growth of the feather, which is an incautious reader might gather from Mr. Simpson's seriously reduces the value of the plumes to the farmer. lepler, behave as if it were glued to the surface of the The imperfection, technically known as “barring,” takes cirh.
the form of a series of narrow, chevron-shaped bars or In my letter of April 22 I illustrated my point by con
malformations across the whole feather. The general dering the analogy with the case of ionised air between appearance of a moderately affected plume is shown in the itru parallel piates maintained at a constant difference of accompanying photograph (Fig. 1). Examined closely, it putential. As this comparison is inaccurate, I shall take is seen that the regularity of the individual barb is much the liberty of putting the case in another way, in the hope
disturbed at the bars, and that the barbules are there hilt it may prove more convincing. The earth is to be defective and only partly differentiated from the barbs. **Puded as a conducting sphere which is continuously The appearance is such as to suggest that the barbs have ***Flying a negative charge in certain areas-probably
been constricted at these particular regions, and that in the threr in which rain is falling-and losing it again by con
development of the feather the barbules have failed to sinction through the atmosphere from all the rest of its
become differentiated and open out, though with a needle surtare. Since the observations on the earth's field only
their separation can sometimes be effected. Occasionally tatry to Enf-weather regions, we need only consider what several barbs will remain joined together at the bars, they hap Over them. There will be an earth-air current also having failed to differentiate. In many z nich under specified conditions, will have attained a of the barbs are shortened, the missing part having broken atract value, the charge on the earth's surface being
i The statistics are taken from a paper by the Hon. Arthur Denglass at reacired to give the necessary potential gradient to read before the recent meetings of the British Association at Cape Town. write the current. Suppose that by some means the Mr. Douglass is the author of a well-known work, “Ostrich Farming in esisatın at some distance from the surface suffers a
South Africa," and was one of the pioneers in the domestication of the jermanent increase locally, whilst the air close to the
Ostrich, and probably the first to hatch the chicks hy artificial incubation.
His death shortly after the meetings of the Association, is a great loss to suiiare is unaffected. It is clear that, whatever view is the agricultural and political life of Cape Colony,
off at one or other of the bars, showing these to be places doves, after hatching, were altei nalely starved and fed for of weakness.
some days at a time when the feather was in process of The extent of the barring varies much on different birds formation, with very remarkable results. On the feathers and according to locality and season. Sometimes all the developing, similar bars were produced in very striking wing, tail, and covert feathers are affected, while in others fashion and in great profusion. The results of the experionly a few plumes exhibit the imperfection. Again, the ments were such as to leave no doubt that the barring in number of bars different feathers varies greatly ; this case was due to malnutrition or some disturbance in frequently they occur at fairly regular intervals along the the metabolism of the bird. entire length of the feather, or only a few are present and The ostrich farmer, however, is convinced that inthe rest of the feather is perfect. Where the barring is sufficiency of food is not the only factor involved. Freclose, a single barb will be irregular at five or six places quently bars appear on the feathers of birds which apparalong its length. The deficiency can be overcome to a ently have been well fed all the time. A general opinion large degree by juxtaposition in the process of " dressing' prevails that the ostrich fly, Hippobosca struthionis, is before the feathers are retailed, but buyers estimate that, often responsible for the trouble, and also the ostrich mite, as a result of the presence of the bars, the value of the Pterolichus bicaudatus, both of which sometimes infest the feather to the farmer is frequently diminished from 20 per birds in large numbers. It is difficult to see how these cent. to 50 per cent., probably an average of about 25 per external parasites can act directly upon the feather germ,
As the trouble is very general over all the ostrich- but it is undoubted that the progressive farmer who dips farming districts in South Africa, it is manifest that the or sprays his birds against the pests produces a plumage subject is one which calls for thorough scientific investi- much less subject to imperfections, and consequently of gation.
higher value. Whether the fly or mite can affect the The development of the ostrich feather has not yet been feather directly or only indirectly by lowering the general
condition of health of the bird is a subject for investigation, as is also the influence of the tape-worms and thread-worms (Strongylus douglassi) which frequently infest the animals. The influence of in-breeding and heredity will also have to be considered. It is significant to find that a similar barring occurs on the ostrich farms in Pasadena, Cali. fornia, among birds which have been ill fed, and the trouble is general on the ostrich farms in Florida, where conditions are not so favourable for birds. A inuch rarer defect is where the parts of a feather have failed to differentiate along one or more vertical lines extending the whole length of the vane. This irregularity is in all probability the result of some permanent injury to the feather germ or its socket, and occurs independently of the nutritive condition of the bird.
The production of these irregularities in the growth of feathers as epidermal derivatives is of much zoological interest in connection with pathological conditions of epidermal structures generally. As is well known, the enamel of the teeth of children is frequently grooved or pitted in transverse rows, a condition which can usually be traced to some error in feeding, congenital disease, or ailments affecting the general nutrition of the body during the time the teeth were forming; the finger nails are often transversely grooved after an illness or injury, pointing to a response to malnutrition; hair frequently breaks, falls off, or changes in character after an illness from the same cause; the horns of cattle and antelopes occasionally show one or more narrow constrictions representing a diminution in the amount of horny material. All these defects can be correlated with some low condition of health of the animal at the time, and serve to establish that the imper fections in the feathers of Ostriches are not an isolated phenomenon, but, mutatis mutandis, can be compared with imperfections in the epidermal products of other vertebrates.
While it may be rash to predict before the experiments
in hand are completed, yet from the facts already known Fig. 1.-Ostrich feathers showing barring.
there seems good reason for expecting that the trouble will worked out, but from our knowledge of that of feathers
be found to rest very largely with the farmer, and that
the remedy will be mainly a question of a proper and generally there can be no question that the barring represents some interference with the normal growth of the
regular supply of food—not an easy matter in time of plume at an early stage, an interference which prevents
droughts. Without question there exists an extremely
sensitive relationship between the production of a perfect the proper differentiation later of the feather into rachis, barbs, and barbules; moreover, these must recur from time
feather and the proper nutrition of the bird ; artificial to time during the growth of the feather. As to the cause,
selection in breeding may also assist towards the production
of a strain in which the feathers are less influenced br the evidence mainly points to impaired nutrition of the
constitutional changes in the bird. J. E. DL'ERDEX. feather germ during its early stages. Farmers universally Rhodes l'niversity College, Grahamstown, acknowledge that an insufficiency of food during the time
Cape Colony. the feathers are forming, as from a drought, will result in a plucking full of barrings, breakages, and other malformations. In a general way it is recognised that the
Origin of the Term “Metabatic." better fed the bird the less likely are its feathers to show My attention has been directed to the word melabatic as any defects. Furthermore, from correspondence with Dr. relating to the transfer of energy. I should be much obliged R. M. Strong, of the University of Chicago, who has been
if anyone could give me information as to the author of engaged upon a study of the development of feathers for the term, the date of its introduction, or any scientific years, I learn that experiments have been conducted by paper in which it occurs in such form as to betoken its Prof. c. 0. Whitman and himself upon malformations in exact meaning,
ROBERT E. BAYNES. other birds exactly similar to those of the ostrich. Ring- Christ Church, Oxford.
THE PEARL FISHERIES OF CEYLON.
water, the young brood is frequently, if not generally,
destroyed by the action of currents or by being overT! HE important series of reports on the pearl-oyster whelmed by sand, so that the oysters never attain
fisheries and on the marine biology of Ceylon, maturity. These circumstances naturally suggest that prepared under the direction of Prof. Herdman, which the transplantation of young brood oysters in large is being published by the Royal Society at the request quantities from the outer exposed beds to the inner of the Colonial Government, continues to grow both ones, which are favourable for their growth and dein size and value. Parts iii. and iv. have been recently velopment, will be a highly profitable operation in issued, and although in the preface to part iii. Prof. those years when the inner beds do not receive a Herdman expresses the hope that the whole will be natural fall of spat. Such transplantation constitutes completed in four parts, this has not proved possible, one of the principal recommendations which Prof. and a fifth part is now contemplated, to contain the Herdman and Mr. Hornell make for the developconcluding sections of the pearl-oyster work, several ment of the fishery, and work on these lines has more supplementary reports of a faunistic character, already been commenced, although in 1905 it was and a general discussion of the faunistic results. not particularly called for, excepting on the grounds
The two parts of the pearl-oyster report now under actually cleared during the fishing of the year, owing review give a summary of the results of the more to a very extensive natural fall of spat on all the recent investigations and inspections carried out by beds which had taken place in the autumn of 1904, Mr. Hornell on the banks in the Gulf of Manaar, Other practical measures which are recommended together with an account of the pearl fishery of 1905, include "cultching," or the deposit of suitable solid which proved to be far in excess of any recorded fishery, material, such as shells or broken stone, to which the both in the number of men and boats engaged, and in young oysters can attach themselves, the thinning out the quantity and value of the oysters taken, the of overcrowded beds, and the cleaning of the oyster nearest approach to
it being the fishery of the previous year, 1904.
Prof. Herdman and Mr. Hornell have been exceedingly fortunate in being able. so soon after the commencement of their inrestigations, to study the exact conditions under which these two most successful fisheries have been carried out,
and although they state that it does not seem likely that the 1905 results will be rivalled by any prospective fishery of the oysters now in sight upon the grounds, ver the knowledge and insight into the nature of the factors leading to a great and profitable fishery which have been obtained will be of the very highest value in
Fig. 1.–Natural cultch (Lithothamnion), and, to the left, a similar Nullipore ball with a dozen young pearl
oysters attached. From "Report to the Government of Ceylon on the Pearl Oyster Fisheries of the suggesting rational meas- Gulf of Manaar." ures for the future control and improvement of the beds; and a careful perusal of banks by means of the dredge, thereby removing in Prof. Herdman's reports leaves little doubt that in the as large numbers as possible such enemies of the case of these pearl-oyster beds, practical measures oysters as starfishes, and also other animals which carried out upon a sufficiently large scale under ade- would compete with the oysters for the available quate scientific control will be capable of effectively supply of food. preventing, in most years, such total failures of the If we may venture upon a word of suggestion, we fishery as have been so often recorded in the past, and
hope that in the concluding volume of ensuring to those engaged in the work" a much Prof. Herdman will furnish us with a concise and more certain and uniform return for the labour and sufficient summary of the whole of the pearl-oyster capital employed.
reports, since from the nature of the circumstances The investigations already made show clearly that in which the series has been produced it is a little the different beds or “paars are subject to very difficult to extract from them the essential features of different conditions, and whilst some, which the valuable work accomplished. We wander along specially favourable for the growth and development of pleasantly enough with Prof. Herdman on his explorthe oysters, are liable to receive only a small and inade- ations in the Gulf of Manaar, and accompany Mr. quate fall of "spat,” others almost invariably become Hornell with pleasure during his inspections of the covered at the breeding season with an abundant supply pearl banks from year to year; we traverse many an of the young brood. Since, however, the latter beds agreeable by-way under Mr. Hornell's direction, and are situated further seawards and close to the deeper not infrequently retrace our steps along the same paths i "Report to the Government of Ceylon on the Pearl-Oyster Fisheries of
with Prof. Herdman for our guide; we are allowed to the Gulf of Manaar." By Prof. W. A. Herdman, F.R.S. With Supple.
see, as it were, the ideas gradually developing in the zentary Reports upon the Marine Biology of Ceylon by other Naturalists. minds of the two investigators, and we watch with l'art til, pp viii + 328 and plates: and part iv., pp. xvi+242 and plates. Published at the request of the Colonial Government by the Royal Society,
interest the new facts and suggestions of Mr. Lardan, 1903.)
Hornell's various letters and reports becoming gradu
ally assimilated into Prof. Herdman's general scheme- light might have been thrown in the country visited all of which would be entertaining enough on a warm by Mr. Pratt in his furthest journeys; but, reasonable afternoon in summer, when we lay on some grassy as are these claims to consideration and forbearance, cliff within sound of the sea, but is, it must be con- and difficult and trying as the present writer know's fessed, a little trying to busy individuals anxious to the Mekeo hinterland to be, they do not palliate the arrive at the kernel of the business in hand.
publication of such a mass of misstatements and Of the supplementary reports in parts iii. and iv. inaccuracies as occur in this book, and are absolutely the most important is probably Prof. Dendy's mono- excuse for such apparent "faking” of photograph on the sponges, which occupies some two graphs or drawings as produce the ridiculous results hundred pages and is illustrated with sixteen plates. shown in the plates facing pp. 168, 262, and 268. Prof. Dendy describes 146 species from Prof. 'Herd- Again, with a perversity that is as determined as man's collection, of which 77 are new, and he con- it is misplaced, in the map given at the beginning of siders that the most striking feature of the sponge- the volume a number of such well-known Mekeo fauna of Ceylon, next to its richness, is its close villages as Aipiana, Inawi, and Rarai are bodily relationship with that of Australia and the adjacent transferred from the right to the left bank of the islands. On the other hand, it differs considerably St. Joseph River, to which Nara village is shifted from the sponge-fauna of the Red Sea, as well as from
some twenty miles northwards of its actual site. that of the south and east coasts of Africa.
Certain of the more glaring inaccuracies in print In the case of the Alcyoniidæ, on the other hand, and picture may now be specified. Prof. Arthur Thomson notes that there is a great The description on p. 71 of Motu pot-making is difference between the Ceylon collections and those
inaccurate, nor are “ several hundred large dug-out made off the Maldives by Mr. Gardiner and off New
canoes brought together and moored side by side at Britain and New Guinea by Dr. Willey.
the landing stages in groups of six or seven (p. 72) It is impossible to refer in detail to all the memoirs
to form the lakatoi used on the annual Motu trading in these volumes, which contain descriptions of a great number of new or little-known species, and it expedition to the Papuan Gulf. The present writer would be premature to attempt to anticipate the
has seen many Motu dances, and in 1903 watched the
departures of a number of lakatoi from Port Moresby, general discussion on the fauna of Ceylon which Prof. Herdman promises for the concluding part of the
but certainly never saw a Motu girl“ spin round with
a dizzying rapidity," and finds it difficult to believe report. All the memoirs are well illustrated with a number of lithographic plates, of which the very borne out by the plate, obviously a photograph, he
that Mr. Prati did; while Mr. Pratt's statement is not beautiful series accompanying Mr. E. T. Browne's account of the Medusæ may be specially mentioned quotes in support of it. as doing credit to artist and lithographer alike.
The plate facing p. 168, with its attached legend, "A piebald tribe : The Motu-Motu people of Hoods Bay : .." constitutes perhaps the most gro
tesquely erroneous statement in the book, and is not THE ABORIGINES OF UNEXPLORED NEW unworthy of an imaginative traveller of the fifteenth GUINEA.
century. The plate shows two natives, irregularly IN N this work Mr. A. E. Pratt gives an account of spotted with patches of white, wearing a form of
the time he, with his son, a youth of seventeen, perineal bandage which is not worn at Hulaa or anyspent in New Guinea collecting zoological specimens where on the Hood Peninsula; and the accompanying during the years 1901–3. A short visit was paid to letterpress is scarcely less frankly imaginative; "the the Dutch settlement of Merauke, newly established piebald people are one of the mysteries of New among the Tugeri tribes of Netherlands New Guinea Guinea,” says Mr. Pratt, “and their origin is unexto check the raids into British territory of these enter- plained. The origin of a piebald tribe in Hood Bav prising savages, but owing to the unsettled condition is pretty obviously in the fertile imagination of the of the country no attempt to leave the settlement was author, who calls the tribe he has brought into existmade. - Mr. Pratt then shifted his quarters to Port
ence the Motu-Motu, this as a matter of fact being Moresby, in British territory, whence moving to Yule
the Motu name for the Toaripi of the Papuan Gulf Island he organised his expeditions to the mountainous living about 150 miles west of Hood Bay. hinterland of the Mekeo district of the Central
Of course albinos,” though they never have pink Division, where almost the whole of his time was eyes, occur sporadically all over New Guinea, and are spent and where his collections were principally made. particularly abundant at Hulaa, where there are at A large number of new Lepidoptera, a new fish, and
least four of these “ albinotic" individuals. But a couple of new reptiles rewarded Mr. Pratt's efforts; apart from elderly folk, in whom leucoderma of the but although the object of the expedition was
hands and feet, spreading to the forearm and leg, is collect zoological and botanical specimens, Mr. Pratt | by no means rare all over British New Guinea, the devotes little space in his book to natural history, its writer, who has twice visited Hulaa, knows of but bulk being given to a gossipy description of the one case of partial albinism, a child of about eight author's journeyings, with remarks, too often in years of age belonging to the Sinaugolo, a tribe in accurate, on the natives he came in contact with. no way closely related to the Hulaa folk.
Mr. Pratt on p. 291 points out that he cannot The astounding and wildly unnatural plates which pretend to be a trained ethnologist . . . " while his face pp. 262 and 268 cannot be passed without remark.
notes, too, were fragmentary owing to the A glance at the latter plate will convince anyone stress of · journeyings and the
pressure of that it represents no tropical jungle, while the whole work. ..."
story of the fishing-nets spun hy spiders on bamboo In these circumstances it is easy to forgive the loops erected for this purpose in the jungle, which omission of any mention of many problems of the these two plates illustrate, seems to be a far-off greatest interest, e.g. the provenance of the Mekeo reminiscence of the kite-fishing with a bait of spider's stone adze and “ pineapple club, upon which some web which skips along the surface of the water I "Two Years among New Guinea Cannibals." By A. E. Pratt, with
practised in the D'Entrecasteaux and other archi. Notes and Observations by his Son, H. Pratt. Pp. 360 ; illustrated.
pelagoes off south-eastern British New Guinea. There (London : Seeley and Co., Lid., 1906.) Price 16s. net.
are many other inaccuracies and misstatements in the