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Mitra striatula, Lam.
(Voluta Barbadensis, Gmel.)
Voluta musica, Linn.

Fam. Convoluta.

Ovula gibbosa, Lam.
(Bulla gibbosa, Linn.)
Cypræa exanthema, Linn,
cinerea, Gmel.
bicallosa, Gray®.
Spurca, Linn.
pediculus, Linn.

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DESCRIPTION OF SOME NEW FOSSIL SHELLS FROM BISSEXHILL AND SPRINGFIELD IN BARBADOS.

Fig. 2. Nucula Packeri.

Fig. 3. The same, showing the dorsal margin.

Oliva conoidalis, Lam.
Conus verulosus, Brug.
ranunculus, Brug.s

Fig. 1. Scalaria Ehrenbergi.

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Fig. 4. Nucula Schomburgkii.

Fig. 5. The same, showing the dorsal margin.

FAM. SCALARIANA, Lam.

SCALÁRIA EHRENBERGI, E. Forbes. (Fig. 1.)

S. testâ brevi, obesâ, ventricosâ, anfractibus 5, longitudinaliter costulatâ, costis

1 A rare shell in the recent state about Barbados, but common among the Virgin Islands. Fossil specimens are frequently met with in marl-pits.

2 Rare around Barbados, but common amongst the Virgin Islands. They are found abundantly in marl-pits, with the colour of their aperture as well-preserved as if they had only recently come out of the sea.

3 Found frequently imbedded in the coral rock in the neighbourhood of Bridgetown, and near Black Rock.

4 Rare in the fossil state.

5 Rather rare in the fossil state, but abundant in the sea around Barbados. My fossil specimens are from the Hope in Christ Church parish.

6 Rare in the fossil state.

7 I have not been able to determine these three species of Cypræa.

8 Rare in the fossil state.

regularibus æqualibus, lamelliformibus, in ultimo anfractu 16; aperturâ rotundatâ marginatâ.

Shell ventricose and shortly conical, whorls about 5, rounded, longitudinally ribbed; the ribs equal, elevated and not thick, numerous, 16 on the body whorls: no spiral ridge on the base: marginal rib of the round aperture strong and high; columella broad and rather angulated at the base. Length of an inch breadth of an inch.

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This remarkable species is allied to some tertiary forms, probably miocene. Among recent species its nearest ally is the Scalaria crassilabrum of Sowerby, jun., a species from the Philippines and Central America.

I found this unique shell near the summit of Bissex Hill, imbedded in siliceous limestone. I am glad that my discovery of this new shell has afforded Professor Forbes an opportunity to name it after the learned Professor Ehrenberg, who, by his discovery of a new class of animalcules in the rocks of Barbados, has added another claim to our thanks for his indefatigable researches into the history of the most minute forms of organic life.

Mr. Edward Packer of Springfield forwarded to me during my stay in Barbados, a specimen of rock consisting of dark gray limestone enclosing small quartz pebbles, in which numerous shells of the genera Nucula, Lucina, Pleurotoma and Venus were so firmly imbedded as to form one mass. According to his description, this block lies isolated in the neighbourhood of Springfield, and I do not recollect having met with a similar rock in situ during my rambles in the island. I have to regret that the specimens of shells which I received from Mr. Packer were mostly very imperfect; this refers chiefly to the Lucina and Pleurotoma. One of the species of Nucula was very perfect, which, at my request, my friend Professor Forbes has named after Mr. Edward Packer, a gentleman who has taken great interest in my researches while in Barbados, and offered me many facilities in prosecuting them.

I have consented, not without some hesitation, to the specific name of the second species, upon which my kind friend Professor Forbes has insisted.

FAM. ARCACEA, Blainv. and Lam.

NUCULA (LEDA) PACKERI, E. Forbes. (Figs. 2 and 3.)

N. testâ oblongâ subtumidâ, transverse striatâ longitudinaliter obliquè unisulcatâ; latere postico productiore, attenuato, angulato, subacuto; antero rotundato; margine ventrali simplici, subsinuato; lunulâ oblongo-lanceolatâ, carinis elevatis cinctâ.

Shell ovate or oblong, rather tumid, produced slightly retrally into a subcompressed acutely-angled beak, which is separated from the rest of the shell by a shallow furrow; the other extremity is rounded. The surface is crossed by very numerous transverse stria with sharp intermediate ridges. The beaks

are prominent. The lunule is well-defined and smooth, and bounded by two ridges, one of which is the margin of the upper part of the valves. The margins of the shell are smooth. Transverse dimension of an inch: beak

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to frontal margin of an inch.

This form is allied to several existing tropical and sub-tropical Nuculæ, and to some crag forms.

NUCULA SCHOMBURGKII, E. Forbes. (Figs. 4 and 5.)

N. testâ ovato-ellipticâ, valdè inæquilaterali, tumidâ, posticè rotundatâ, anticè abruptè truncatâ, lineis sæpè divaricatis sculptâ ; umbonibus subterminalibus; lunulâ lanceolatâ, marginibus denticulatis.

Shell rather tumid, ovate, elliptic, very inequilateral, with the beaks nearly terminal at the truncated anteal extremity. The posteal extremity rounded. An arched furrow runs from the beak to the margin at the anteal extremity. This furrow is smooth; the space in front of it is terminated by about a dozen nearly perpendicular curved grooves, bounding a somewhat impressed, nearly smooth indistinct area. Between the arched groove and in front of the border of the lunule, all over the shell are fine curving divaricating furrows, forming a series of elegant angular markings. Towards the cardinal margin these furrows curve inwards, widen, and have thicker interspaces, so as to denticulate the borders of the lanceolate and nearly smooth lunule. The ventral margin appears to have had smooth lips. The cast is smooth. Dimensions of the most perfect specimen, from beak to posterior angle, central breadth

thickness.

This remarkable shell belongs to a group of Nuculæ, of which there are few known species, either living or fossil. The oldest known members of the section occur in cretaceous strata: Nucula bivirgata, Sowerby, and Nucula ornatissima, D'Orbigny, both gault species, are examples. Still nearer the West Indian species is the Nucula Cobboldia of the crag, a species which lived on in the Celtic region of Europe till the elevation of the sea-bed of the glacial epoch caused its extinction. Two living Nuculæ represent this group, viz. Nucula divaricata and Nucula castrensis, both described by Mr. Hinds in the Zoology of the Voyage of the Sulphur'; the former was taken in twentyfour fathoms in the Chinese seas, and the latter dredged in seven fathoms, sand, at Sitka in North-West America.

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CHAPTER III.

THE APPLICATION OF THE MINERAL PRODUCTS OF THE ISLAND OF BARBADOS, AND THE COMPOSITION OF ITS SOILS.

THE existence of several mineral products in the Scotland formation becomes evident from the preceding remarks. They have in a great measure been hitherto unheeded, and the gift of nature has lain there profitless. The author of the numerous valuable contributions in the Agricultural Reporter,' signed with the initials J. D., and which are known to be the productions of Dr. Davy, the brother of Sir Humphry Davy, has repeatedly drawn the attention of the inhabitants to the great advantages which might be derived from some of the marls in the improvement of such soils in Barbados as are deficient in carbonate of lime, and also as a valuable article of export, especially to British Guiana, a country remarkably deficient in limestone. Dr. Davy asserts that he knows of no limestone procurable in any part of England so fitted for agricultural purposes as the chalk and soft calcareous marl of Barbados.

It is not likely that Barbados possesses precious metals. Hughes relates that on the surface of the earth on Colonel Abel Alleyne's estate (in St. James's parish), a piece of ore had been found which upon analysis in England proved to contain a large proportion of gold; but though diligent search was made by digging and otherwise no more was discovered. That author mentions another instance of some ore reported to have been found by Dr. Bruce, without the locality where he found it being known. The north-eastern point of St. Peter's parish is another locality where gold is said to have been discovered, but we possess no proofs of the truth of such assertions. The ore found on Colonel All estate might have been dropped there by accident after having been brought from South America. It is mentioned by Sloane, that the Duke of Albemarle, who possessed a patent authorizing him to search for mineral treasures in all the West India plantations belonging to England, made great inquiries after minerals in Barbados without success, except that they found some substance at a hill which was very shining and was lodged in the earth; some of it was afterwards sent to Jamaica, but proved to be only white or silver-coloured Marcasite (pyrites), which on trial held no metal, or so little as not to be worth while to look after'. Smoky gray clay ironstone (compact clayey oxide of iron combined with carbonic acid) is abundant about Chalky Mount, Mount Hillaby, Jeeve's, &c.

1 Sloane's Natural History of Jamaica, vol. i. P. 33.

The occurrence of bituminous coal in various situations in the Scotland formation called Manjack', has been alluded to in the geological sketch. There are several varieties of combustible matter intermediate between the liquid mineral tar and the bituminous coal, which, according to Dr. Davy's examination, pass in a series from mineral tar through soft bitumen and hard asphaltum into "glance coal," by which name he calls "a mineral substance which possesses the essential character of this coal, viz. not melting when heated, but swelling up from partial fusion and caking, to use an expression commonly applied to bituminous coal of this quality; burning for some time with flame and leaving a portion of cinder or coke, which of course consumes without flame." The consideration of the geological structure of the Scotland formation led Dr. Davy to make some remarks on the probability of finding serviceable beds of coal in certain parts of this island. Such a supposition is borne out by various circumstantial proofs, derived not only from the mineral character of the rocks which compose the district, but from the presence of the tar springs which owe their origin to "woody and vegetable substances which may have undergone by the agency of subterranean fires, those transformations and chemical changes which produce petroleum, and this may, by the same causes, be forced up to the surface, where, by the exposure to the air, it becomes inspissated, and forms the different varieties of pure and earthy pitch or asphaltum3." This mineral oil occurs in most countries where coal is found4. Mr. Crawford, on a voyage up the Irawaddi to Ava, collected numerous geological specimens which are described by Dr. Buckland in the Geological Transactions; and alluding to the resemblance which some green and yellow sandstone from Prome bore in their mineralogical character to the plastic clay formation, he observes that near Pugan and Wetmasut they were associated with brown coal and petroleum, precisely as they are found containing brown coal all over Europe, and connected with wells of petroleum near Palma, and also in Sicily. Near the petroleum wells of Wetmasut, Mr. Crawford also found large selenites, resembling those which occur at Newhaven in the plastic clay. In Ava, as in Europe, they seem to be co-extensive with the clay-beds of the tertiary formation5.

The carburetted hydrogen or fire-damp which escapes through the soil at Turner's Hall Wood, although it does not necessarily indicate the

1 "In several places of America these sorts of bitumen are found and have several names; the most common name is Mountjack, by which it is known very well amongst the privateers."-Sloane's Natural History of Jamaica.

* Barbados Agricultural Reporter for January, 1846.

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3 Lyell's Principles of Geology (5th edition), vol. i. p. 335.

4 The most powerful springs producing petroleum hitherto known, are those on the Irawaddi in the Burman empire. In one locality there are said to be 520 wells yielding annually 400,000 hogsheads.

* Geological Transactions, 2nd series, vol. ii. p. 388.

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