tions of yeasts, bacteria, &c. ; it must also be firm, strong, and readily taken to pieces and sterilised by heat.

He has accomplished this by taking a piece of thick-walled glass tubing, about inch in diameter and 3 inches long; the two ends are softened and slightly drawn to narrow tubes, not too thin. The piece of glass now looks like a narrow tube with a thick-walled bulb in the middle. One face of this central bulb is then ground flat, until a hole about inch in diameter is cut through; a similar hole is then ground in the opposite face of the bulb. The apparatus is now ready to be put together.

It is sterilised at 150° C., and cemented by paraffin (or by gelatine in acetic acid), by one of the ground faces, to a broad glass slide properly sterilised. Sterilised cotton-wool is stuffed into the two narrow tubulures, and the hanging-drop culture, properly prepared on a sterile coverslip is cemented (by means of sterilised oil, vaseline, or paraffin, &c.) over the upper hole of the chamber.

The apparatus is now ready for use if the culture is required in air only; a slow diffusion of air and retardation of evaporation may be insured by simply wetting the cotton-wool in the tubulures with pure water.

If it is necessary to pass gases into the culture, one of the stuffed tubulures is connected by means of caoutchouc tubing (sterilised in corrosive sublimate, absolute alcohol, and boiling) with the appropriate gas apparatus. The pressure can be regulated by the stuffing in this, the proximal tubulure, and by clip or screwtaps. The stuffed exit tubulure is also protected by caoutchouc tubing and a clip.

If a very strong cover-slip and careful cementing are employed, the author finds that a very good partial vacuum can be obtained, and even retained for some hours. This is very useful in cases where it is necessary to remove the oxygen or carbon-dioxide from the imprisoned atmosphere. This may be accomplished more or less readily by attaching bulbs containing an alkaline solution of pyrogallic acid, or a solution of potassium hydrate. Obviously the apparatus can also be used for testing the effect of poisonous gases, or for observing the action of light of different intensities, or of various low temperatures, and so forth. Obviously, also, it may be used for testing the action of different coloured lights, and of darkness, &c., with certain simple modifications, e.g. employing different coloured glass tubing, or opalescent or blackened glass for making the culture-chamber, and adding various screens, covers, &c., as required.

10. On some Simple Models illustrating the Vascular System of Vertebrates. By Professor W. N. PARKER.

11. On the Progress of the Investigation of the Natural History of the Friendly Islands. By J. J. LISTER.

At the meeting of the British Association at Bath in September 1888, a Committee was appointed for the purpose of taking steps for the investigation of the Natural History of the Friendly Islands and other groups in the Pacific visited by H.M.S. Egeria.

I was then starting to join the Egeria, and a grant of 100%. was voted to assist me in carrying out the object of the Committee. At the next meeting the Committee reported that I had joined the Egeria on her arrival at Tonga and was carrying on my researches.

I beg leave to offer the following brief account of the further steps that I took in pursuance of my object.

H.M.S. Egeria arrived at Tongatabu on May 23, 1889, and after a short visit to the neighbouring island of Eua, I left Tonga for a cruise among the islands lying to the northward, between Tongatabu and the Equator.

In the course of this cruise the Egeria called twice at Samoa, and also visited Viti Levu, the principal island in Fiji, and made surveys of Fakaofu in the Union Group, and Canton (or Mary) Island in the Phoenix Group, besides touching at several of the neighbouring islands.

On returning to 'Tonga I had the opportunity of visiting Falcon Island, which was thrown up by volcanic eruption in 1885, and some of the other less accessible islands of the group.

After the departure of the Egeria in November, I paid two visits to the Vavau Islands in the northern part of the Tonga group, and owing to the courtesy of Mr. S. Parker of Eua I stayed two weeks with him on that island.

I finally left Tonga on April 24, 1890, and returned to England at the end of the following September. My collections have been disposed of as follows:

The geological specimens have been placed in the Woodwardian Museum at Cambridge. Specimens of the skins and eggs of the rarer birds and my collections in other groups of animals, in the British Museum of Natural History. The collections of dried plants, in the Herbarium of the Royal Gardens at Kew. A small collection of the skulls of the natives of Fakaofu and Tonga in the Museum of the Royal College of Surgeons.

The examination of the material is still in progress, but the following papers have appeared:

'Woodwardian Museum Notes, Sections IV. and V. by Alfred Harker, M.A., F.G.S., Geological Magazine,' April 1891.

6

'Rocks from the Tonga Islands,' by the same author, Geological Magazine,' June 1891;

together with the following by myself:

'A Visit to the newly-emerged Falcon Island, Tonga Group,'' Proceedings of the Royal Geographical Society,' March 1890.

'Notes on the Natives of Fakaofu,' read before the Anthropological Society, March 1891.

'Notes on the Birds of the Phoenix Islands,' read before the Zoological Society, April 21, 1891.

'Notes on the Geology of the Tonga Islands,' read before the Geological Society, June 24, 1891.

FRIDAY, AUGUST 21.

The following Report and Papers were read:

1. Report of the Committee nominated for the purpose of arranging for the Occupation of a Table at the Zoological Station at Naples. See Reports, p. 365.

2. On some Species of Diatoms with Pseudopodia.

By J. G. GRENFELL, F.G.S., F.R.M.S.

The diatoms are two small species of Melosira and Cyclotella Kützingiana, which occur mainly as isolated frustules and are non-motile. They have been found in London, Hertfordshire, and Wiltshire. The pseudopodia are delicate, often invisible till the material is dried on a cover glass. Comparatively thick ones are occasionally found. Gentian violet and methylene blue are good stains for them. The pseudopodia are apparently non-retractile, generally straight, sometimes branched, but those of the earliest gathering in April were often repeatedly branched. Their number is fairly constant. Most of them are placed fairly synmetrically round the edge of the valves. The length varies from two-and-a-half to nine times the diameter of the frustule. The diatoms are sometimes connected by broad bands which seem to be anastomosed pseudopodia. Very similar bands

This paper includes the description of the specimens collected by Captain C. F. Oldham, R.N., in his survey of 1890.

are found amongst the Heliozoa. The protoplasmic nature of the pseudopodia is inferred from the following facts ::

They are destroyed by nitric acid and by a low red heat; they give no cellulose reaction with Schultze's solution or with iodine and sulphuric acid; they stain readily with Kleinenberg's hæmatoxylin; they also stain with borax carmine, picro-nigrosin and alcoholic saffranin. Pseudopodia similar in shape are found amongst the Heliozoa generally, but pseudopodia agreeing with these in the minutest details are found on some specimens of Archerina Boltoni, a Heliozoon which occurred in vast numbers with the diatoms in London. Other as yet undetermined Heliozoa occurring in the same water have very similar pseudopodia.

3. On Nuclear Structure in the Bacteria. By HAROLD WAGER.

Owing to the small size of the cells in the bacteria, the presence of a nucleus, or of anything akin to nuclear structure in them, has not yet been satisfactorily demonstrated. Dr. P. Ernst, has, however, described certain bodies which to him appeared to be of the nature of nuclei, inasmuch as they possessed a reaction towards reagents different from that observed in spores.

It is interesting to note that in the closely allied group of the Cyanophycea, Scott and Zacharias have been able to detect structures resembling a nucleus.

According to Bütschli, the central portion of the protoplasmic contents of the bacterium cell is to be regarded as of the nature of a nucleus, in that it takes up very readily certain aniline dyes. It should be noted, however, that such stains as hæmatoxylin, carmine, saffranin have but little staining power for the contents of the bacterium cell, compared with such stains as gentian violet, fuchsin, &c., which stain them deeply, but which also stain the protoplasm of the cells of higher plants almost as deeply as the contents of the bacterium cell. This seems to show that the bacteria contain very little of the chromatic substance which is found in the nuclei of the higher plants. The author of this paper has for some time been working at the bacteria in the hope of elucidating this point, and has obtained a bacillus in which a distinct nuclear structure can be observed.

The bacillus referred to forms a thin scum on the surface of water containing Spirogyra in a state of decay. The cells, which consist of short rods, occur either singly or in pairs. They are about 25 to 3 μ in length, and from 13 to 1.5 μ in diameter, and when seen in a fresh state one or more brightly refractive granules can be observed in each cell. In cover-glass preparations stained with fuchsin, all stages in the division of the bacillus could be observed. The preparations should be made during the earlier stages of the development of the scum on the surface of the water, while the bacillus is in a healthy state of division.

In the centre of each cell a substance deeply stained by the fuchsin is found. This in young cells consists of two rods placed side by side, with a less deeply stained substance between them, the whole being surrounded by a very thin membrane which is only visible at the two ends. This is the structure which we may call a nucleus. It is surrounded by a space containing a substance which is only slightly stainable, and this again is surrounded by a deeply-stained membrane, outside which is the slightly stained gelatinous envelope. Previous to its division the cell elongates; the nucleus also elongates and contracts slightly about the middle of its length. A dumb-bell shaped structure is thus obtained. The two rods divide completely, so as to form two groups, containing two rods each, which remain connected together for some time by the less deeply-stained portion of the nucleus. The constriction becomes more and more pronounced, until finally the two halves of the nucleus are completely separated. The outer capsule or cellwall has meanwhile been contracting towards the middle, the contraction keeping pace with the division of the central mass. This contraction goes on until at a certain stage a delicate transverse partition appears, dividing it into two; each half contains one of the halves of the original nucleus. Ultimately the two halves become completely separated, and two new cells are formed.

In the majority of cases the cells are completely separated before the division

of the nucleus again begins, but in many instances the nuclear rods were seen to be dividing in cells which were still connected with each other.

After a time the division of the cells takes place less rapidly, and finally ceases altogether. The division of the nucleus becomes very irregular, and at the time when cell division has ceased the nucleus has become broken up into granules which are distributed irregularly in the contents of the cell.

This breaking up of the nucleus appears to be preliminary to the formation of spores, although the formation of spores has not been satisfactorily observed.

5. A Discussion was held on the Systematic Position of certain Organisms that are regarded by some Naturalists as Animals, and by others as Plants.

SATURDAY, AUGUST 22.

The following Papers were read :—

1. On Anatomical Nomenclature. By Professor W. KRAUSE, Göttingen.

6

The subject of the paper, Anatomical Nomenclature,' may seem to be only of interest to the anatomist in the dissecting-room. This is, however, an error, for the names of several parts of the body occur in every branch of Biological Science, Zoology, Embryology, &c., and especially in the practice of Medicine and Surgery. There have been and there are many complaints that a great many parts of the body have not one but several different anatomical names, for instance-conarium, pineal body, epiphysis. This state of things has every year become worse and worse; in Germany, especially, it has become almost insupportable.

The reason is obvious. Germany was and is not united in the administration of the internal affairs of the single states, and every state, and even every little university, has had and has to-day its own anatomical nomenclature. If one compares the anatomical papers and the handbooks of different nations, one meets with the same difficulties. In Germany, however, there are still greater difficulties to face. Here in the same university sometimes different anatomical nomenclatures exist. Much time and labour are lost by student and teacher owing to these differences.

This labour is completely lost, because it is and it must be of little importance whether this or that name be given to a particular muscle or a particular artery. Sometimes confusion and misunderstandings arise, but the worst is that the mere reader is unwilling or does not care to translate the anatomical terms of an author, foreigner or otherwise, into his own anatomical terminology. So reading becomes superficial; the reader understands the words but not the real meaning of the author. This state of things cannot last, and so a Committee has been elected for preparing, not a new one, but at least a homogeneous nomenclature. This Committee consists of seventeen anatomists, of whom twelve are Germans and four or five from other countries. Sir William Turner from Edinburgh and Professor Cunningham from Dublin represent Great Britain. This Committee has begun to work in earnest, and has already done much. The author referred to a little paper, only three pages, which contains nothing but the names of the muscles of the human body, but much work had to be done before it was completed. Now Germans can, at least, answer the question, if a foreigner should ask, 'What is the German name for a certain muscle?' A year ago no German anatomist could have given any answer but 'I do not know, some call it the trapezius, others the cucullaris.' In conclusion, the author said, ' In two or three years we shall have finished the whole, and then we shall ask the anatomists of other countries to give their candid opinion on the results of our labours.'

Some general principles have already been laid down by the Committee.
Firstly: The name should be as short as possible.

Secondly: Personal nomenclature should not if possible be used. There are some anatomical names which are known in every country, as 'Hunter's canal,' but a great many are known only in one country. There are little nodules on the margin of the semilunar valves of the pulmonary artery: some call them 'nodes of Arantius,' others the 'nodes of Morgagni'; but Arantius certainly never saw them. There is a prominence on the external ear of man, in Germany known as 'Darwin's prominence,' but in England it is often called ' Woolner's tip,' and so on. Thirdly: No part of the body should have more than one name; more synonyms only cause confusion. This name shall always be a Latin one; every nation can afterwards easily translate it after its own fashion. Latin is the only real international language, and by adopting it we hope to have a sound foundation.

་

NOTE.-Anyone who may wish to have a copy of the paper referred to above is requested to apply to the author.

2. On Fertilisation and Conjugation Processes as allied Modes of Protoplasmic Rejuvenescence. By Professor MARCUS HARTOG, M.A., D.Sc., F.L.S.

3. A Preliminary Classification of Sexual and allied Modes of Protoplasmic Rejuvenescence, &c. By Professor MARCUS HARTOG, M.A., D.Sc., F.L.S.

I. The following modes of rejuvenescence occur in cellular and in certain apocytial organisms:

A. PLASTOGAMY: the fusion of cytoplasts into a plasmodium, the nuclei remaining free (Myxomycetes).

B. KARYOGAMY: the union of cells (gametes), cytoplast to cytoplast and nucleus to nucleus, to form a 1-nucleate cell, the zygote. The following variations occur:

1. ISOGAMY. The union of gametes undistinguishable in size, form,
and behaviour; this may vary as follows:-

(a) MULTIPLE: between several gametes (up to 6).
(b) BINARY: between a pair of gametes;

or, from another point of view

(c) INDIFFERENT: between any gametes of the species.

(d) EXOGAMOUS: between gametes of distinct broods only (Ulothrix).

(e) ENDOGAMOUS: between gametes of the same brood only (Hydrodictyon).

2. ANISOGAMY: the union of two gametes differing chiefly in size; the smaller (micro-) gamete is male, the larger (mega-) gamete, female. 3. HYPERANISOGAMY: the female gamete, at first active, comes to rest before fusion with the male (Lower Melanophycea).

4. OOGAMY: The female is never actively motile; the male is termed a spermatozoon, the female an oosphere.

From another point of view karyogamy is

5. ZOOIDIOGAMOUS: one gamete at least is actively motile (flagellate, ciliate, or amoeboid).

6. SIPHONOGAMOUS: karyogamy is effected by a tubular outgrowth from one or both of the gametes (Phanerogams).

1 Examples are only given in cases where it is necessary, from the introduction of new terms, or where the examples are not generally familiar.