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lamina, in which line also it opens externally by a few ramusculi, like the interseptal canals. 2nd, the interseptal canals, two in each interseptal space, which arise respectively from the great spiral canals of the preceding turn, and terminate on the inner aspect of the cord close to the chamber where they divide into branches which join the marginal plexus, the great spiral canals, and open externally on the surface of the cord, respectively. 3rd, The marginal plexus, which occupies the marginal cord, and is formed of an intricate net-work of canals derived chiefly from branches of the great spiral and interseptal canals, which net-work is spread throughout the cord, and, as before stated, opens in all directions over its surface. 4th, A system of small canals, which open on the surface along the lines of the great spiral canals and interseptal spaces, and are in connection with the spiral and interseptal canals respectively.
Animal.-- This, as was discovered by Dujardin, is a Rhizopod, which fills more or less all the chambers and canals of the test, besides spreading over its surface externally, hence M. A. D. d'Orbigny was not far wrong, when he stated, or M. de Férrussac did for him (Ann. des Sc. Nat. t. vii. p. 100, 1826), “que le test de ces petites coquilles était entièrement renfermé dans le corps,” though he was wrong for the time in taking the rhizopodous extensions for the arms of a cephalopod, as he subsequently admitted. The chambers consist of cavities of this sarcode which are more or less filled with propagative spherules, &c., which will be more particularly mentioned directly ; and they communicate by short branches with the great spiral and interseptal canals, the marginal plexus, and with each other through the interseptal spaces, besides opening on the surface, through the vertical tubuli.
The sarcode of the canal-system is also more or less tubular, and thus affords a transit for the contents of the chambers externally ; probably however not "tubular,” as the word is generally understood, but sarcodal, through which the substances are transmitted as in Amoeba.
Besides the propagative spherules, the chambers contain starch in grains and amorphous, which still more nearly allies the Foraminifera to Spongilla and probably all the sponges, for as starch abounds in the former it may be assumed to be present also in the latter. Whether the chambers contain any other than the propagative organs, remains for future research to determine. They not improbably each, also, contain a nucleus.
As regards nutriment, this may be enclosed by the sarcode and a stomachal cavity extemporized for digestion, at any part, while the injesta may be ejected through the sarcode direct or through the larger tubes of the canal-system. Lastly the smaller canals, which open over the great spiral canals and interseptal spaces, may be for admitting water into the larger ones, and thus afford a water-circulation.
Propagative spherules. These are produced in the chambers, and are of two kinds, viz, large and small.
The small spherule is composed of a homogeneous sphere of matter (slightly tinged yellow by iodine) which is enclosed in a delicate, transparent, spherical capsule, and attached in massive groups to branched stems like grapes, while the large spherule consists of a sphere of granular substance equally tinged yellow by iodine, and sometimes also surrounded by a transparent, delicate, spherical cell. The former are about 1-5400th and the latter 1-1800th inch in diameter. The chambers may be more or less filled with both kind of spherules together or separately, and the smaller may be the earlier stage of the larger, if they be not sperm-cells; while they may be also observed on their transit to the exterior, in all parts of the canal-system even to the vertical tubuli, where their elongation in the fossil species (Nummulites) at once points out their softness and adaptation in this respect to the sizes of the canal through which they may have to pass ; but from being of different sizes below the largest abovementioned, they, for the most part, take the largest or smallest tubes for outlets according to their size. This variation in size may also account for the variation in size of the primary cell of the full-grown species; which is sometimes as small nearly as the smallest spherule, and at others much larger than the largest. Those which are observed about the test externally are white when dry, so that they already contain calcareous matter. Sometimes the spherule or primary cell begins to develope a second while still in the parent chamber (I have seen this in the outer turn of Nummulites, indeed I have the section showing it), and then the young one evidently becomes too large for passage through the ordinary channels. In this case it would seem that a special opening is formed for their exit through the spiral lamina, for holes exist here and there in this part of the test, which, from their rounded edge, indicate that they were made by the animal. Not unfrequently these are formed opposite the great spiral canals.
Mode of development.— The spherule having left the parent becomes the primary cell of the new being, and putting forth a stolon, produces another chamber, and so on until a certain number are formed which are arranged horizontally around the first, and the Operculina developed.
The stolon, therefore, forms part of the canal-system, and the chambers are in this manner developed from it. As development progresses, the chambers which bud from the margin of the cord, attain their largest size, and then begin to diminish again, until they end in nothing almost, which is closed in, as before stated, by the bending down of the marginal cord and its union with the preceding turn, when the test is thus hermetically sealed and its form completed. The union between the chambers at their bases is probably filamentous, for the chambers do not here communicate with each other, while the calcareous septa which divide them are frequently united to the marginal cord, and if not in direct contact, they are always more or less scolloped, indicating a filamentous layer of the sarcode which previously existed between them and the cord; besides, we shall sèe presently that the development of the test is frequently continued on without the presence of the chambers, so there can be no question that all other structures are developed from the sarcode of the canal-system, or from the filamentous sarcode, connected of course originally with a nucleated cell, the germcell. Hence the filamentous sarcode becomes analogous to the mycelium of Fungi, and being rhizopodous, is united, through the Sponges, to the fungal parasitic animals which inhabit the cells of Algæ, and are propagated by monociliated Amoebe; and through the latter, to the true Fungi, which are propagated by defined sporules.
Nummulites is nothing but a more complicated form of Operculina type. The chambers bud from the margin of the cord and extend outwards and inwards until they reach the level of the margin of the last turn and the umbilicus of the test respectively; the last three, four, or more, being of successive sizes, up to the last of all, which is least developed.
The same principle obtains in the formation of the test and propagation of Orbitoides dispansa and Orbitolites Mantelli, Cart. (Orbitoides Mantelli, d’Orb.); but the canal-system is different, and there are no columns of condensed shell-substance in the latter. In Orbitoides disa pansa each chamber is united to the two in front and the two behind it by stolon-processes as in Cycloclypeus, Carp., and there is an annular canal behind each row which is united by straight, transverse, interseptal or intercameral branches with that in front and behind it, in each half of the test.
The latter system also exists in Orbitolites Mantelli, but the stolunprocesses are represented by oblique canals which gyrate from the centre to the circumference, and thus unite each chamber with the two in front and two behind it; while as the chamber becomes elongated
towards the circumference, the oblique canals are increased to 2, 4, and 6, in number in the outer rows, one above another, so as to resemble their disposition in Orbitolites, as shown in Dr. Carpenter's diagram. In the annular canals we cannot help seeing the analogues of the great spiral canals in Operculina and Nummulites Ramondi, &c., if not in all nummulites; while in the stolon-processes of Orbitoides dispansa and the oblique canals of Orbitolites Mantelli, we seem to have a combination of the marginal plexus and interceptal canals, for they both open ultimately at the margin or circumference of the tests respectively. The columnar chamber-structure on the other hand in both, which corresponds with the vertical development of nummulites, that is the extension of the chambers to the umbilicus on each side the horizontal plane, is united by ascending and horizontal stolon-processes which indirectly give exit to the propagative spherules, throughout; for the same kind of spherules are developed in both the chambers of the horizontal plane and those of the columnar structure, even to the very centre of these fossils, as in Nummulites and Operculina.
The tests of Conulites and Orbitolina lenticularis, are developed upon the same principle as the rest, and both present the same kind of propagative spherules in their chambers. Conulites however, has the same columnar chamber-structure and columns of opaque shell-substance as Orbitoides dispansa, but with a helical layer of chambers externally something like the horizontal layer of Nummulites; while Orbitolina lenticularis has no columns of opaque matter in its columnar chamberstructure, and has a cyclical arrangement of the rows of chambers externally, like that of the horizontal plane in Orbitoides dispansa and Orbitolites Mantelli, and the rows in Orbitolites complanata.
Alveolina meandrina, and therefore, A. elliptica, are developed upon the same principle as nummulites would be if elongated vertically. The former has an interseptal system and marginal plexus of canals and the latter too, probably. In Alveolina elliptica the greater part of the test is often without chambers, so that its development is as often wholly carried on by the sarcode of the canal-system, and the same is frequently the case with the last turns of the globose forms of nummulites, e.g. N. perforata ; while in Alveolina elliptica also, the chambers sometimes disappear and reappear at intervals, leaving the spire to go round by itself in the meanwhile ; as exemplified also, in the annular canals of Orbitoides dispansa and Orbitolites Mantelli. These are the instances to which I have before alluded as evidencing a development of the chambers upon the sarcodal filaments of the canals.
Art. V.-Short Memorial of the Honorable Mountstuart Elphin
stone, and of his Contributions to Oriental Geography and History. By John Wilson, D.D., F.R.S., Honorary President of the Society.
Read on the 9th May 1860.
It is not the object of this short paper to present to the Society a regular biographical sketch, however short, of the distinguished individual to whom it refers. Its aim is merely that of expressing our obligations to his valued patronage, and to his own literary efforts for the illustration of Indian Geography and History. It is principally for the sake of order that the date of a few of the more prominent incidents of his life is here given.
Mountstuart Elphinstone was the fourth son of the eleventh Baron Elphinstone, by Anne, daughter of the third Lord Ruthven. He was born in 1779, and was educated partly by a private tutor in his own family, partly at the High School of Edinburgh, and partly at a private school near Kensington. In his early days he was more distinguished for his animation and activity than for that eager and diligent application to study which he exhibited in after-life. He left England for India in July 1795. His first appointment in this country was that of Assistant to the Magistrate of Benares. After being about four years in that office he was transferred to the Political Department of the Public Service, of which he was destined to reap the highest honours. By Lord Wellesley, by whom he was early appreciated, he was appointed, in 1801, Assistant to the Resident at Puná, Colonel Barry Close, an able military and diplomatic servant of Government. He was present, with his superior officer, at the negotiation of the treaty of Bassein in 1802, and he was soon called upon to witness important military proceedings to which, in defence of the Péshwa from the rival Maráthá powers, that treaty gave origin. In August 1803 he became Secretary to Sir Arthur Wellesley at Ahmadnagar : and with that prince of warriors he was in the thick of the battle of Asáyi and other engagements which followed. By Sir A. Wellesley, who formed a high opinion of his talents and sagacity, he was recommended to the charge of the