OCR Text |
Show 31 LIICUT.-COL. H. H. GODWIN-AUSTEN ON [Jan. 6, The central tooth is much shorter and smaller than the laterals, is tricuspid (fig. 3 b), the two outer cusps being just below the centre point; in one specimen dissected, owing to the central part being much worn, this central tooth is evenly tricuspid (fig. 3). The laterals rise from long narrow plates, and are very pointed, with an outer and inner cusp some distance below the apex, being thus also tricuspid ; the outermost laterals are very nearly unicuspid (fig. 3 a). The jaw is curved, but has no central projection (fig. 4). This shell was placed by von Martens in the genus Macrochlamys; and looking at its shiny glassy shell, so very like many in the Indian region, I should certainly have done the same; yet the animal differs from that genus not in one but in several characters-externally in the absence of the long shell-lobes ; internally in the odontophore and jaw; and in the reproductive organs it is widely separable, Macrochlamys not possessing the spicula amoris. In searching through Semper's work for characters approaching those now figured and described, I observe the nearest, as might be expected, in those genera found in the islands of the Malay Archipelago and not in those found to the westward in India. On plate iii. figs. 1, 2, Reise im Archipel d. Philipp., is shown the sagitta amatoria of Tennentia philippinensis and Parmarion pupillaris, from Java, the same type. This I would submit is an indication that the slug-like forms of this part of the world are the descendants of these glassy Helices, just as we find the general anatomy of Girasia, a slug-like species of India, to be like that of Macrochlamys, and that although the outward form of both animal and shell is very similar respectively, the races of the two areas have a most remote relationship. How far these characters of Everettia and Dyakia extend around this area is yet to be discovered. We cannot as yet say with certainty that shells with similar internal structure do not exist in India; they are certainly absent in the N.E. Himalayas and Khasi Hill Ranges, but there are numbers of even large species in Southern India yet to be examined, and of which we know as yet nothing. Of the shells of New Guinea we are also quite ignorant, at least I have not seen any work on their anatomical variations. EVERETTIA CONSUL. Helix resplendens (Philippi), Metcalfe, P. Z. S. 1851, p. 70(?). Helix consul, Pfeiff. P. Z. S. 1854, p. 289; id. Monogr. Helic. iv. p. 44 (1859), et v. p. 97 (1868); id. Novitat. Conch, iii. pi. lxxiv. figs. 13, 14 ; Reeve, Conch. Icon. pi. cxcviii. fi». 1395 (1854). r ° Macrochlamys consul, Wall. P. Z. S. 1865, p. 405. Nanina consul, v. Martens, Preuss. Exp. Ost-Asien, Landschneck p. 240(1867). EVERETTIA JUCUNDA. (Plate III. fig. 1.) Helix jucunda, Pfeiff. P. Z. S. 1863, p. 524; id. Novitat. Conch. m. pi. lxxiv. figs. 11, 12 ; id. Monogr. Helic. v. p. 101 (1868). |