. The Cambridge natural history. Zoology. Fig. 81.—Cypraea moneta L., showing tentaculae at edge of mantle, which partly envelops the shell: Si, siphon; M, M, mantle; F, foot; T', tenta- culae at edge of mantle. (After Quoy and Gai- mard.) x f. Fig. 82. — Monodonta canali- fera Lam., New Ireland, showing mantle lobes. (After Quoy and Gai- mard.). When a G-landina seizes its prey, the palpae (see Fig. 83) appear to enfold it and draw it in towards the mouth. It is in the Opisthobranchiata that the organs of touch attain their maximum development. Many of this group are shell-less or possess a s
. The Cambridge natural history. Zoology. Fig. 81.—Cypraea moneta L., showing tentaculae at edge of mantle, which partly envelops the shell: Si, siphon; M, M, mantle; F, foot; T', tenta- culae at edge of mantle. (After Quoy and Gai- mard.) x f. Fig. 82. — Monodonta canali- fera Lam., New Ireland, showing mantle lobes. (After Quoy and Gai- mard.). When a G-landina seizes its prey, the palpae (see Fig. 83) appear to enfold it and draw it in towards the mouth. It is in the Opisthobranchiata that the organs of touch attain their maximum development. Many of this group are shell-less or possess a small internal shell, and accordingly, in the absence of this special form of defence, a multiplied sense of touch is probably of great service. Thus we find, besides the ordinary cephalic tentacles, clusters or crowns of the same above the head of many Nudibranchiata, with lobe-like pro- longations of the integument, and tentacular processes in the neighbourhood of, or surround- FiG. 83. — Glandina . ,, , i- ^ -r^- m ir.^s seizing its prey, mg the Draiicmae (see i^igs. 58 and 84), or with buccal papii- even proiectinc^ from the whole upper surface lae turned back. „ . ^, *'- .^. _ -^- (Strebei.) of the body (Fig. 5, C). m In the Pelecypoda, the chief organs of" touch are the foot, which is always remarkably sensitive, espe- cially towards its point, the labial palps on each side of the mouth, and the siphons. In certain cases the mantle border is prolonged into a series of threads or filaments. These are par- ticularly noticeable in Pecten, Lepton^ and Lima (Fig. 85), the mantle lobes of the common L. Mans of our own coasts being very numerous, and of a bright orange colour. In many genera — Unio^ Maetra — this sensibility to touch appears to be shared by the whole mantle border, although it is not furnished with any special fringing. The ' arms' of the Cephalopoda. Please note that these images are extracted from scanned page images that may have been dig
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
