THE MONTHLY MICROSCOPICAL JOURNAL. NOVEMBER 1, 1870. I.-On the "HEXACTINELLIDE," or Hexradiate Spiculed Silicious Sponges taken in the 'Norna' Expedition off the coast of Spain and Portugal. With Description of New Species, and Revision of the Order. By W. SAVILLE KENT, F.Z.S., F.R.M.S., of the Geological Department, British Museum. (Read before the ROYAL MICROSCOPICAL SOCIETY, Oct. 12, 1870.) In the paper it is my privilege to communicate to this Society on the present occasion, I propose to give an account of all those sponges belonging to the same group as the beautiful Euplectella, EXPLANATION OF PLATES. FIG. 1.-Pheronema Carpenteri, natural size, showing the basal origin and fascicular distribution of the long anchoring spicula. 2.-Pheronema Grayi, natural size, showing the general and non-fascicular distribution of the anchoring spicula. 3-16 represent spicula from various regions of the same sponge. 3.-Basal portion of an attenuate spinulate spicule from the oscular fringe × 100 linear. 4.-Portion of an attenuate erectly-spined spiculum from the same region × 100 linear. 5.-A filiform adpressly-spined spiculum from amongst the long radiating spicula of the upper region X 100 linear. 6.-A portion of the same still further enlarged. 7.-An irregularly and profusely spined spiculum from the sponge body X 100 linear. 8.-A portion of one of the large attenuate hexradiate spicula from the exterior surface of the sponge body x 100 linear. 9.-One of the "spiculated hexradiate" spicula (Bowb.), having one radius of the perpendicular shaft suppressed, from the interior portion of the sponge × 100 linear. 10. An irregular variety of the same type. 11.-A spiculum of the same type having the terminations of the lateral radii echinate. 12. Another variety of the same form, in which the perpendicular radius, suppressed in Figs. 9 and 10, is greatly produced. 13.-Portions of attenuate spicula from the inner portion of the sponge, inter- 14.-Minute fusiform echinate spicula from the same region × 200 linear. VOL. IV. PLATE LXIV. S or Venus' Flower Basket, and the notorious and frequently inverted Hyalonema, or Glass-Rope sponge or coral, taken during my recent dredging expedition off the coasts of Spain and Portugal in company with Mr. Marshall-Hall and Mr. Edward Fielding, in the former gentleman's yacht, the Norna.' In the first place, however, I feel myself called upon to acknowledge here my indebtedness to the Council of the Royal Society for their kindness in awarding me a grant of 507. wherewith to defray the cost of the necessary dredging and collecting apparatus, and on which it may be said in great measure the success of the expedition depended. The results accomplished will, I trust, convince the Council of the Royal Society that their confidence has not been misplaced. Four of the species, belonging to the interesting group just FIG. 1.-Askonema Setubalense, PLATE LXIV. natural size. 2.-Interlacing fascicles of simple attenuate spicula of which the skeleton is 3.-A portion of one of these simple attenuate spicula × 100 linear. 5.-Another variety, in which the two extremities are slightly clavate and echinate. 6.-One of the larger hexradiate stellate spicula, showing at a how the terminations are occasionally spined, × 100 linear. 7 and 8.-Two of the smaller hexradiate stellate spicula, having their terminations profusely spined, x 100 linear. 9.-One of the multiradiate spicula of the sarcode x 200 linear; at a one of terminations of the radii still further enlarged. 10.-A fragmentary form discovered among the other spicula, but of uncertain origin, x 100 linear. 11.-An ideal restoration of the same. 12. The basal skeleton of Farrea occa, in a perfect condition, natural size. 13.—The meshwork forming the basal skeleton, viewed from above, × 40 linear. 14. The same viewed obliquely. 15.-A furcate spiculated biternate interstitial spiculum (Bowb.), from F. occa, × 50 linear. 16. A spiculated biternate variety × 40 linear. 17.-A small attenuato-stellate spiculum × 300 linear. Figs. 15, 16, and 17, are copied from Dr. Bowerbank's "Monograph of the Siliceo-fibrous Sponges," Proc. Zool. Soc.,' 1869. 18.-Aulodictyon Woodwardi, natural size, attached to a piece of Lophohelia 19. A fragment of the reticulated meshwork of the skeleton x 50 linear. 21.-One of the attenuate "tension" spicula, having one of the extremities inflated and recurvato-pellate and dentate, × 200 linear. 22.-Portion of a variety of the same type, having the pellate expansion replaced by recurved uncini. 23.-A free attenuate hexradiate spiculum, with one extremity slightly inflated, × 100 linear. 24. One of the minute " spinulo-quadrifurcate hexradiate stellate" spicula of the sarcode x 200 linear. 25.-A termination of a radius of the same, still further enlarged. PLATE LXV. cited, out of a total number of nine collected, are altogether new to science, and two of these are described here for the first time. In addition, I am enabled by examination of the material amassed to add considerably to our knowledge of the history and structure of those species already introduced. Pheronema Grayi, W. S. Kent. Most conspicuous in the whole series is the fine sponge described under the above name in the 'Annals and Magazine of Natural History' for August last. This beautiful form is known to the fishermen of Setubal as "Ninos de Mer," or "the Sea Bird's-nest;" it bears a strong family likeness to the interesting form dredged up last year by Drs. Carpenter and Wyville Thomson in the Shetland seas, and described by the last-named gentleman in the Philosophical Transactions' as Holtenia Carpenteri. Unfortunately, the generic name proposed by Dr. Thomson has to give way to that of Pheronema; Dr. Leidy, an eminent American naturalist, having previously described as Pheronema Annæ a sponge evidently PLATE LXV. FIG. 1.-Lanuginella pupa, shown at a, natural size, attached to a calyx of Lopho helia prolifera. 2. A specimen detached x 12 linear. 3. Interlacing attenuate hexradiate spicula, of which the framework of the skeleton is composed, x 100 linear. 4. An isolated spiculum, with unequally developed lateral radii, similarly magnified. 5.-Two of the minute spinulo-multiradiate spicula of the sarcode x 200 linear. 6.-A supposed reproductive gemmule × 100 linear. 7.-Another and possibly more advanced form, similarly magnified. 8.-A fragment of the smooth reticulated fibrous skeleton of Aphrocallistes 9.-A still more slender and irregularly stellate portion of the same. 12. A simple attenuate hexradiate variety × 100 linear. 13.-One of the porecto-triradiate spicula of the sarcode x 100 linear. 15.—A minute attenuate, adpressly-spined, spiculum of the sarcode x 100 16.—A portion of the reticulate and echinate skeleton of Aphrocallistes Beatrix × 100 linear. 17.-A lateral view of a fragment of the same, showing the spinose prolongations, similarly magnified. 18.-One of the porecto-multiradiate spicula × 100 linear. 19.-A "verticillately-spined" spiculum of the sarcode x 100 linear. 21.-An attenuate hexradiate spiculum, with one of the radii spinous, referred possessing the same generic characters as the one subsequently described in the 'Philosophical Transactions.'* As a species, my sponge differs from Pheronema Carpenteri in many points. In the first place, in the invariably more or less globose contour of its body, and in its large and outwardly expanding oscular orifice. In Pheronema Carpenteri the sponge body is usually sub-cylindrical, with an entirely cylindrical osculum. Another distinction is evidenced in the origin and distribution of the long, silvery, hair-like, anchoring spicula, which, spreading out on all sides, serve to fix the sponge in the treacherous ooze from which it was taken. In Dr. Wyville Thomson's species these originate in a number of distinct fascicles springing from the lower portion of the sponge, while in my own they are distributed equally throughout the greater portion of the external surface, without having any definite fascicular arrangement. Dr. J. E. Gray has considered this character sufficient for the institution of a new genus for its reception; but without committing myself to that extent, I regard this feature as an auxiliary and important one in proof of its specific individuality. But in addition to the readily recognized characters of external contour, there are others afforded by the internal spicular structure that assist us in discriminating between this form and Pheronema Carpenteri. Having examined the spicules of both species I have failed to find in the last-mentioned one the long attenuate spinulate forms which are present in mine, and also long attenuate erectly-spined ones, which likewise occur in Pheronema Grayi. I may also remark that the shafts of the recurvato-birotulate spicula (Amphidisci, W. Th.) are more profusely echinate in Pheronema Grayi than in P. Carpenteri. This more or less spinous character of the skeletal elements may be quoted as being of very great service in the specific diagnosis of many other forms; as, for instance, between Aulodictyon fecunda and another species of the same genus I shall presently introduce. The specimen exhibited this evening, in company with about a dozen more examples, was procured with the aid of the fishermen's hooks at a depth of, at least, 600 fathoms. On first being brought on board, the sarcode investing and constituting the sponge body was of a brilliant orange colour, a hue remarkably predominant among the Protozoa, while their long, hair-like, anchoring spicula hung about them in matted tresses, cemented together by the * Since writing my first paper descriptive of Pheronema Grayi, I have seen Dr. Leidy's representation of his species ('American Naturalist,' March, 1870). That it is generically identical with the one described by Prof. Wyville Thomson, I have no longer any doubt, and must even consider it to be very closely allied specifically; it possesses the same cylindrical outline and the same fascicular arrangement of the anchoring spicula. The smooth upper surface of Dr. Leidy's sponge is evidently owing to its having undergone a considerable amount of wear and tear before it was deposited in his museum. I possess a specimen of P. Grayi similarly denuded. tenacious ooze of the ocean's bed. By careful washing these unkempt locks have been disentangled, and the true origin and distribution of each separate glassy filament been made manifest, while at the same time numerous other delicate organisms have been set free which at first appeared to be inextricably held captive in their mazy embrace. Among these were a quantity of a beautiful transparent Pecten (P. vitreus), numerous specimens of a fragile Ophiurid, and a whole host of Foraminifera, which may some day form the subject of a separate communication. Plate LXIII., Fig. 2, represents Pheronema Grayi treated as above described, and Fig. 1, in the right-hand corner, illustrates Pheronema Carpenteri under similar conditions. The remainder of the Plate is occupied by figures of the spicula most characteristic of the first-named species. The sponge I have next to call attention to, though being an indirect result of the expedition, is scarcely less wanting in interest than the form last alluded to. While engaged in inspecting the numerous treasures contained in the Lisbon Museum of Natural History, my attention was arrested by some dilapidated hat-like bodies, of a whitish-brown colour and felty consistence, which occupied a considerable amount of space on the well-filled shelves. Professor du Bocage, the talented Conservator of the Museum, informed me that Professor Wyville Thomson had recently examined these organisms, and had communicated to him his opinion that they were vegetable and not animal structures. The eminent Professor of Belfast had probably only commenced his sponge studies at that period, otherwise he would hardly have failed to recognize the essentially spongious nature of their tissues. A lighted match, applied by my friend Mr. Fielding, determined on the spot the silicious consistence of the framework of one of the objects of our suspicions, and a subsequent microscopic examination on board the yacht, of a piece kindly placed at my disposal by Prof. Bocage, established beyond doubt the correctness of our premises, while at the same time it revealed to us that we had lit upon a sponge altogether new to science. We may proceed to summarize its technical peculiarities as follows: Askonema, nov. gen.,* W. S. Kent. Sponge body, bag- or cup- shaped, of felt-like consistence; composed of an interlacement of long filiform silicious fibres or spicula. Interspersed among these, hexradiate spicula of various sizes and minute multiradiate ones with capitate extremities. [While the revise of this paper passes through my hands, I avail myself of the opportunity of expressing my conviction that "the lovely lace-like vase form, upwards of three feet in diameter at the * άσкós, a bag; vnua, that which is spun. |