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(Plates LXIV. & LXV.) Read April 5th 1866. r7 1 HE genus Kaphzcs mas established nearly a century ago by Guettard, for the Serpuln nrenaria of Linnzus ; but nothing would appear to have been known about the animal forming the shelly tubes until some years later, when Mr. Griffiths favoured Sir Joseph Banks with an account of a large number of specimens taken on the shore of the lorn island of Battoo, about twenty leagues distant from the coast of Sumatra, after a severe earthquake which occurred there in 1797. These were described * as found stick- ing out some 5 or 10 inches from the hard mud, and covered by from one to three fathoms of water; one specimen measured 5 feet 4 inches in length, and 9 inches in circum- ference at its tail. The animal was not observed, further than that it protruded, from the two apertures at the apex of the shell, tentacula resembling small actinize. In the same volume of the Philosophical Transactions there is a paper by Sir Everard Home, ‘‘ On the Shell of the Sea-worm from the Coast of Sumatra, proving it to belong to a species of Teredo.” Sir Joseph Banks believed it to be a Teredo ; and this opinion, Sir Everard Home says, was confirmed by the discovery of the two recent valves, and the two flattened opercula inclosed in one of the specimens. The entire of the paper, however, is taken up with a description of Teredo mauaZis (?T. noruegica) ; and although the palettes figured on plate xii. (figs. 4 & 5), are very fair representatives of those since ascertained to belong to Kzphus, yet figure 6, of the recent shell of the Teredo, might represent almost anything. While the mere removing of this animal (or at least of its shelly tube) from the Annelida to the Mollusca was a step in the right direction, still another half-century elapsed before anything more was known about its structure or affinities ; and for all that we do know of it from that time until the present, we are indebted to the researches of one to whom all naturalists owe verymuch, Dr. J. E. Gray of the British Museum. From the examination of an apparently perfectly closed specimen of the shelly tube, Dr. Gray was led to believe that the animal of Kuphus was distinguished from all other Lamellibranchiate Mollusca by the absence of true shelly valves ; and in the ‘ Proceedings of the Zoological Society’ for 1557, p. 257, he proposed the genus Purcella for its reception, with the following amended characters :- FURCELLA,Gray.-Animal without any true shelly valves ; siphonal palettes distinct, large, apex dilated, transverse, spathulate, with a central midrib and an elongated, slender, cylindrical base. Tube clavate, irregular, sometimes bent ; apex with two tubular siphonal apertures, separated by a broad hard shelly longitudinal dissepiment ; base pierced with small scat- * Philosophical Transactions, 1806, part 1, pp. 269-274, pls. x. and xi. VOL. xxv. 4H 562 PROFESSOR E. P. WRIGHT ON THE TEREDIDB. tered perforations ; end iiiclosed by two overlapping convex septa, arising from the sides and completely closing the ends. These arched terminal plates appear to be absorbed before each period of activity, and the end is again closed with similar plates at each period of rest, after a sufficient elon- gation and enlargement of the tube for the protection of the enlarged animal, which lives sunk in sandy mud on the shores of tropical climates. These emended characters of Dr. Gray have been adopted by all recent writers on the subject. Thus Messrs. 1%.and A. Adairzs, in their iinportant work ‘ The Genera of Recent Xollusca,’ pp. 331-648, regard the genera Teredo,Linn., and Kuphus, Guettard, as the two genera of the subfamily Teredininse ; and Mr. Tryon, in his elaborate monograph of the family Teredidz *, divides the family into three subfamilies :-I. Teredinae, containing all the recent Te~*edinesexcept Kuphus ; 11. TeredinidE (fossil), and 111. Kuphinae, this latter characterized as cc without valves, tube clavately cylindrical, sunk horizontally in sand, never penetrating timber ;” and suggests that Teredina may indicate a passage from the free and perfect valves of Teredo, through its less important valves eventually becoming merely a portion of the tube, to Kuphus, where the valves are wanting, or are replaced by the cleft shelly plate which closes the lower end. Mil. Tryon had very probably, at the tinie of reading this memoir, not seen a further paper by Dr. Gray in the ‘ Proceedings of the Zoological Society of London’ I-, in which he points out the danger of arriving at conclusions on imperfect premises ; for he proceeds to describe two specimens of a large shell-bearing Teredo from some of the Dutch colonies of the Indian Ocean, that, so far as its palettes were concerned, bore a very close resem- blance to Furcellcc (Kuplms). The palettes of these specimens are described as being of precisely the same form and nearly of the same size as those figured 2 of Ktqhus ure- ~zcwiz~s;but instead of having a small tubercle on the middle of the inner side of the dilated head, each palette is produced into an elongated process about half an inch long, which is more slender and oblong at the base, thicker, flattened, and dilated above, and truncated at the top. The valves closely resemble those of Teredo muwulis, morvegica, and others, but are larger. Not wishing to pronounce positively that this animal belongs to the genus Purcellu, Dr. Gray named it provisionally T.furcelloides. I am inclined to think, on a careful examination of these speciiiiens, that this species of Dr. Gray is the same as, or at least very closely allied to, one described by Dr. A. A. Gould 9 under the name Teredo thoracites, from Tavoy, British Burmah, and for which he afterwards made a new genus, Culobates 11. The palettes are very large and long, stilt-shaped ; the style long and subulate, slightly flexuous, bony, surrounded by a broad dilatation or step, concave on one side and convex on the other, its upper surface deeply excavated ; on this is placed the blade, which is three-fourths as long as the style, thin, linear, oblique, truncated at the tips, about one-third the width of thc stel?. -? I’roceedings of the Academy of Natural Sciences of Philadelphia, 1662, pp. 453-1182. j- IbG1, 1). 313. Proceedings of the Zoological Society, 1857, (Xollusca), plate xxxix. fig. 3. 9 I’roceedings of the Boston Society of Satural History, vol. vi. no. ti, October 1856, p. I>. 1 Ti~on,ioc. c~f.1). 473. PROFESSOR E. P. WRIGHT ON THE TEREDIDB. 563 Up to the present, then, the question remained thus :-the Serpulu uremxiu of Lin- imus was undoubtedly a mollusk, nearly related to the Teredines. Sir Everard Hoi~ic. says that in the tube of 8. { T)crrewric8 both valves and pdettes have been discovered ; and as Sir Joseph Banks probably saw some of Hr. Griffith's recently collected spe- cimens, there is no reason to suppose that this was not really the case. Palettes un- doubtedly belonging to the animal that fabricated the tube have been discovered in it and described by Dr. J. E. Gray. These are identical with those figured by Home ; but no valves were found in Dr. Gray's specimen, though it is very hard to see how they could have been overlooked or lost ; and lastly, Dr. Gray and Mr. Gould have described two species of Teredo which depart in no very striking detail either in appearance or habitat from ordinary well-known shipworms ; and the siphonal palettes of these bear tt certain strong resemblance to those known as occurring in Kuphus. Dr. Gray's speci- mens were in spirit, Mr. Gould's apparently dry. The clearing up of this interesting subject is still a thing to look forward to, the chief point to be determined being the pecu- liarities of the animal inhabiting the tubes of Kzqhzcs cwenarius :-Is it generically the same as a Culobutes tlaoi-mites, Gould, and Teredo furcelloides, Gray, or does it differ from them and agree with Kuphus munnii, sp. nov., hereafter described ? Although unable to settle this point, I still hope that the following description of some very well-marked ship-worms may not be without interest ; and though I wish to express myself with all proper caution on the subject, I believe that, with the additional evidence thus afforded, I shall eventually prove not very far wrong in retaining Kuphus as a distinct genus from Calobates. The following arrangement of the subgeneric forms of Teredo, based chiefly on the form of their siphonal palettes, will show my views more clearly. 1. TEREDO,Linnaxs. Siphonal palettes simple, oblong, transverse, entire, rarely serrated or toothed. I! Izortiegica, Speng., 2'. gzaz'ulis, Linn., 27. megotara;, Hanl., T. excavata, Lukis, &c. 2. NAUSITORA,P. Wright. Siphonal palettes, outer surface convex, covered with thick scale-like striz, inner flat or slightly concave. N. dumlopii (freshwater, India), ? N. smlii, spec. nov. 3. KUPEUS,Guettard. Siphonal palettes with apex dilated, transverse, spathulate, with a central midrib and an elongated, slender, cylindrical base. Xiphons free throughout the greater part of their leIzgth. K. arenarius (Linn.) ?, K. rnuanii, spec. nov. 4. CALOBATES,Gould. Siphonal palettes large, long, stilt-shaped ; siphorns adhereat, omly becomiIzg free at tips. C. thoracites= Teredo furcelloides, Gray, C. australk, spec. nov. 5. XYLOTRYA,Leach. Siphonal palettes elongate, penniform, horny ; lateral edges with short filaments, spongy texture. X. bipinlzccta, Turton, X. Jimbriata, Jeffreys, &c. .fbH 2 564 PROFESSOR E. P. WRIGHT ON THE TEREDIDB. 6.

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