OCR Text |
Show 1 9 0 6 . ] OF SOUTHERN INDIA AND CEYLON. 6 8 7 ancl three of them have been already opened. Nearly all the papillaa have been detached, but are preserved separately. The specimens are dark brownish green, from 15 to 20 mm. long, and from 5 to 7 mm. wide. The papillae are greenish. The largest have a stalk about 2'5 mm. long, and the foliaceous expansion at the top measures about 6 mm. by 5 mm. The edge of the expanded part is symmetrically indented ; from the funnel at its base radiate about five raised tuberculate lines, some of which bifurcate or trifurcate. The grooved and bifid rhinophores are still quite plain, as are also the grooved tentacles below them. From these tentacles runs down a ridge on either side, which seems to mark off the head from the rest of the body. The large tubular anal papilla is on the right side a little below the dorsal margin, and 4-5 mm. from the anterior end. The lateral margins of the foot are expanded; the anterior margin appears to be grooved. There is no trace of any transverse division of the sole, as in Cyerce. The state of the internal organs rendered dissection impossible, but the long pinkish buccal crop was still discernible. The radula consists of 37 teeth, the number mentioned by Alder and Hancock, arranged in a spiral like that represented by Bergh (I. c. plate vii. figs. 2, 3). The outline of the teeth is as represented by Bergh (ib. fig. 4), and they bear 15-18 blunt, truncate denticles. The first four at the base of the spiral are mere plates ; the rest are perfectly formed and increase rapidly in size. According to both the statements and drawings of Alder & Hancock and Kelaart, the dorsal papillae pass round the head and in front of the rhinophores, which they do not do in the other known species referred to Phyllobrcinchus. The preserved specimens do not throw much light on'this point. None of them has any papillae in front of the rhinophores, but it is impossible to say that such papilla? have not fallen off. On the other hand, a comparison with the specimens of Phyl. prasinus collected by me in Zanzibar suggests that the conformation of the head-parts is precisely the same. It is also noticeable that Alder and Hancock complain that the specimens were too hard and brittle for anatomical examination. This suggests that they were then in much the same condition that they are now, and that Alder and Hancock merely repeated Kelaart's statement as to the papilke extending round the head. They no doubt extend up to the lappets connected with the oral tentacles, and, w^hen the animal retracts its head and assumes a circular form, might appear to surround the rhinophores. But it is remarkable that both Kelaart and the Indian artist, whose drawings are certainly not copied from one another, agree in representing the papillae as arising in front of the rhinophores. It is also probable that Kelaart referred the animal to Proctonotus because he thought that the papillae passed round the head. Nevertheless, I think it likely that this species is identical with Phyl. prasinus and Phyl. rubicundus, which do not appear to be differentiated by any marked characters. Kelaart's drawing is P roc. Z ool. Soc.-1906, No. XLYI. 40 |