Wednesday, 9th May.-T. STRETHILL WRIGHT, M.D., President, in the Chair. Various Committees were appointed for conducting special investigations during the recess. Mr George Logan reported that, in accordance with the remit of last meeting, the Committee on Marine Zoology had prepared and forwarded a memorial to the Lord Advocate, praying that certain exceptions be granted on behalf of scientific societies, from the restrictions in the proposed New Herring Fishery Bill. He stated that he had received a reply, mentioning that due weight would be given to the prayer of the memorial. The following donations to the Library were laid on the table, and thanks voted to the donors : Transactions of Royal Society of Edinburgh, Vol. XXII., Part I., 4to; Proceedings of the Royal Society of Edinburgh, 1858-59, 8vo.-From the Society. Proceedings of the Zoological Society of London, 1859. Part III. July to December. From the Society. Board of Science, Second Annual Report (Gold Fields), 1859-60, Victoria; presented to both Houses of Parliament by his Excellency's command.-From David Page, Esq. De la Formation et de la Fécondation des Eufs chez les Vers Nématodes. Par Edouard Claparede. Geneve, 1859. 4to.-Zur Morphologie der Zusammengesetzten Augen bei den Arthropoden, Von Dr Edouard Claparede in Genf.- From the Author. The following Communications were read : I. Observations on British Zoophytes. By T. STREtHill Wright, M.D. On Halcampa Fultoni (Strethill Wright), a parasitic Actinia. The author stated that, in the summer of 1858, he took, by dipping, a great number of Meduse of the genus Thaumantias, off Granton Pier. To the peduncle of one of these was attached a small Actinia, about half an inch in length, and one-eighth of an inch in diameter. From its general appearance, he considered it to be a young specimen of Actinia troglodytes, which had been seized by the Medusa, dragged from its native mud, and brought captive to the surface of the water; but it was unfortunately lost before he could examine it carefully. In June, his friend, Mr Fulton of Granton Pier, brought him some specimens of Thaumantias, to one of which another Actinia, of the same species as the one he had before observed, had attached itself by swallowing the peduncle of the medusa. The body of this Actinia was of a transparent, yellowishwhite colour, and marked by twelve paler lines, indicating the situation of the longitudinal septa within. The oral disc was oval, and formed by the basis of the tentacles and the mouth. The tentacles were twelve in number, of a rich umber brown colour. About one-half of each from the base was marked with five opaque pale-yellow lozenges, and from thence to the top by four bands of the same pale-yellow colour. The brown matter consisted of amorphous, pigment granules, the yellow matter of highly refractive and exceedingly minute molecules, apparently calcaEach tentacle was curved backwards, and resembled the abdomen of a wasp. The pigment could be forced through the top of the tentacle by pressure, indicating an opening at that part. The mouth, instead of being linear, as in the Actinias, tended to assume a quadrangular, or crucial form, though the constantly varying shape of the disc rendered a description of it difficult. The stomach was very peculiar, and differed from reous. Fig. 1. d Diagram of transverse section of H. Fultoni :-a, superior angle of stomach; b b, lateral angles of ditto; c, posterior angle of ditto; dddd, e e, ff, septa; and, gggg, intersepta, uniting stomach with parietes. that of the Actinias. It was a flat and obscurely quadrangular sac in transverse section (fig. 1.) Its angles he should describe as superior (a), lateral (b), and inferior (c.) The superior angle was connected to the parietes of the body by four septa (d), the lateral angles each by one septum (e), and the inferior angle by two septa (f) These septa were continued downwards, as in the actinias, to the lower extremity of the body, and had their free edges bordered by a convoluted ciliated band, furnished with cnidæ, or thread-cells. The stomach and parietes were further connected by four intersepta (g), as he should call them-one between each of the lateral and anterior angles of the stomach, and one between each of the lateral and posterior angles; but these intersepta bore no convoluted bands. The septa probably bore ovaries, or sper maries, the intersepta not, in which case the reproductive system of the animal now described agreed in simplicity with that of the polyp of the Alcyonida, which had only eight septa, each bearing ciliated bands. The upper part of each of the septa and intersepta was perforated by an oval opening, so as to give an uninterrupted passage beneath the tentacles to the circulation of the fluids of the body. By tracing this passage in the Lucernarias, he had come to the conclusion that it was the homologue of the circular canal of the gymnophthalmatous medusa. The attachments of the stomach thus resembled those of the same organ in the other Helianthoid and Alcyonian polyps, but in shape it widely differed from these. In Actinia and Alcyonia the stomach was a flattened sac, open, and evenly truncated at its lower extremity. In the animal now described the lower border of the stomach curved gently downwards from the superior to the lateral angles (fig. 2, a b), and from the lateral to the inferior angle it bent deeply and abruptly downwards (fig. 2, b c), while the last-named angle itself was produced outwards and downwards, so as to form a beaked process, as shown in the figure. The thread-cells of the tentacles are simple and unbarbed; those of the septal bands furnished with a zig-zag thread. When the animal was separated from the peduncle of the Medusa, and placed in a dish of sea-water, it slowly moved from place to place by the aid of the tenacious palpocils which studded the tentacles and upper part of the body, and alternately filled itself like a balloon, and emptied itself by a vermicular contraction of the parietes, which commenced beneath the tentacles, and passed backwards. When dilated, it was seen that the animal was destitute of a sucking disc, and that the posterior part of the body terminated in a funnel-shaped depression, opening into the cavity of the body, and permitting ingress of water therein. During contrac d Fig. 2. d Diagram of lateral view of stomach of H. Fultoni:-a, superior angle; b, lateral angle; c, inferior angle; dd, septa; e e, intersepta. tion, this funnel was everted, and became a cone, through the apex of which the fluid was again ejected. II. On New Fossil Forms from the Old Red Sandstone of Forfarshire. By DAVID PAGE, Esq. (Specimens of the Fossils were exhibited. Mr Page next drew attention to some new fossil forms from the Old Red Sandstone of Forfarshire. These fossils occur in a bed of highly fissile shale, lying in the course of the Powburn, near the church of Farnell, and belong to the gray tilestones, or lowermost series of the system. They consist chiefly of fishes and crustacea-the former embracing three or four species of Diplacanthus, two of Acanthodes, Climatius, Cheiracanthus, and several forms yet undescribed, the latter being Pterygotus, Eurypterus, and Kampecaris, with detached plates, and Parka decipiens. The deposit (discovered some time ago by the Rev. Mr Mitchell of Ferryden) was now being worked out under the superintendence of the Rev. Mr Brewster of Farnell, and Mr Powrie of Reswallie, solely for the fossilsthe noble proprietor, the Earl of Southesk, affording every facility and assistance in the work of excavation. A great number of specimens had been obtained in beautiful preservation, as could be seen from those exhibited to the Society, and geologists might rest assured that every care would be taken to render these treasures available to the purposes of science.* Independent of the paleontological value of so many new and perfect forms, the discovery was of high lithological interest, as enabling geologists to determine with greater precision the relative ages of the Forfarshire and Caithness series, both of which had now been proved to be characterised by the same specific forms. III. On the Nidus and Young of Pontobdella muricata, and other Annelides. By CHAS. WILLIAM PEACH, Esq., Wick. (With Illustrative Sketches.) On the 21st January 1859, my colleague, Collector Boyd, kindly sent me an old oyster shell attached to an oyster, brought to him from the Frith of Forth, on which he had observed something strange and unusual. The form was quite new to me, and although well acquainted with the nests of many shells and other sea animals, this differed from all I had previously seen. I found amongst the nests a small annelid, and, on applying my lens, discovered that it was a young Pontobdella, which I supposed had got in there for shelter. I laid it carefully aside, and continued my examination, and soon found a portion of a second worm protruding from the upper part of one of the nests, and that it, too, was another tiny Pontobdella. This quite surprised and delighted me. Still, I had my doubts whether it had not crept into the nest after it had been accidentally ruptured, and suspected that its errand was one of felonious intent. I then selected a nest which appeared to be full and uninjured. On opening it with my lancet, I found that I had libelled the above-mentioned, for there, snugly coiled up, was another veritable baby Pontob * Several of the fishes referred to by Mr Page have since been figured and described by Sir Philip Egerton in No. 10 of the "Decades of the Geological Survey of Great Britain." Three of the genera are also figured in Mr Page's new work, "Past and Present Life of the Globe." della. Here, then, was a discovery! The Pontobdella is so well known as a parasite on skate and other fishes, that I need not describe it. Remembering how little was really known. about the propagation and early forms of annelides, and of the conflicting opinions entertained by various naturalists on the subject, I felt quite delighted,-some believing that all pass through many changes, from the egg to the adult state; others that there is no change. The tale of the "two travellers" came into my mind, "both are right and both are wrong," and that at any rate an opportunity was afforded me, if appealed to as an umpire, to decide satisfactorily one point in the controversy,—namely, that beyond that of growth, the Pontobdella passes through no change after leaving the egg. The nests are darkish gray, stout and tough, balloon-shaped, are deposited in a group, but not in mathematical order. Although one showed a worm protruding from the top, this was caused by the accidental rupture of the egg; the natural opening for the escape of the young is a circular opening on the side. Each nest contains one worm. The shell having been long out of the water, all the worms were dead, but in a good state of preservation; they, with many of the nests, are in spirits, and only await the time when some one will demand them for publication, in the long desiderated history of these beautiful, but too long neglected creatures. Having given my decision for the no-change man, I must now turn and side with those who assert change. From having read many of the papers, and seen the figures both of the adult and early stages of annelides, by the late Dr George Johnston, and of others published in various volumes of the "Magazine of Natural History" (unfortunately few of these volumes have come in my way), and as well from observations of my own, "On the luminosity of the sea," published in the "Transactions of the Royal Institution of Cornwall for 1849 and 1850," where I figured two forms of the young of annelides which came under my notice during my researches on that subject, as well in 1844, when I first discovered the Nereis bilineata, as a tenant of the same shell with the hermit crab,-Pagurus bernhardus,-I saw the eggs of this Nereis extended, and afterwards sheltering under the appen VOL. II. 2 c |