Mollusca : testacellidæ and zonitidæ / by W.T. Blanford and H.H. Godwin-Austen.

  • William Thomas Blanford
Date:
1908
Catalogue details

Licence: In copyright

Credit: Mollusca : testacellidæ and zonitidæ / by W.T. Blanford and H.H. Godwin-Austen. Source: Wellcome Collection.

    318/352 (page 282)
    descending; aperture much lower than in T. comjpluvialis, eolumellar margin of peristome oblique. Major diam. 11, min. 10, height 5 mm. Hah. South Andaman, Port Blair. [The animal of Taphrospira baihycharax, Bs. MS., a close allv of T. convallata, Bs., from the South Andaman Island, is as follows :— Animal ochraceous, dark grey on the extremity of foot; mucous gland overhung by a pointed termination. Sole of foot divided ; usual peripodial grooves with a broad margin below. The right shell-lobe is long and fairly broad at base, and in life probably very extensible over the shell. The left shell-lobe is very broad and smooth and must spread over a large surface of the shell. The dorsal lobes are all small, the left in two parts, the posterior situated under the left shell-lobe and distant from the anterior lobe. The wall of the branchial chamber is sparsely spotted. The animal examined was in an excellent state of preser- vation, the generative organs at their full maturity. The most notable thing is the absence of the amatorial organ. The penis is elongate, there is a short kalc-sac contiguous to the junction of the vas deferens, followed by a moderately long epiphallus, up to the penis muscle retractor; there is no caecum, the tube bends on itself and soon expands into a convoluted mass with an indis- tinct coiled appearance when looked at with transmitted light, thence it becomes much narrower and leads away towards the generative aperture. The above swollen aperture looks as if we had here the representative of the coiled caecum of Macrochlamys much modified and separated from the retractor muscle. The spermatheca is elongate, and contains three spermatophores beautifully preserved ; the walls of the sac were of necessity much stretched and transparent. The uterus and ovo-testis do not call for any attention. The spermatophore recalls that of Austenia giyas. The flume is very long with a bunch of fine bifid delicate spines at its basal end; for about two-thirds of its length it is straight-edged and spineless, six spines then occur at very equal distances apart, up to the junction of the flume and capsule, which is long and cylindrical, terminating in a thin whip-like appendage, but the cap-like end of the capsule seen in other species is not present in this one. The most striking feature of this spermatophore is the large single antler-like process at the terminal end of the flume, having six points, and these again bifid, very similar in this respect to A. gigas. Jaw semicircular, with a central projection. The radula formula is + 18. 2. 9. 1.9. 2. 18 + + 29 . 1 . 29 + Central tooth tricuspid, admedians bicuspid, of usual form in Macrochlamys.]