. Echinodermata . Fig. 3. Calcareous deposits from Peniagone ferruginea n. sp. a—c from abactinal surface, d, e from actinal surface, /—// from the tentacles, /' from the tube-feet. The body is oval and about twice as long and one half as high as it is broad. The somewhat elongated mouth is situated on the anterior ventral surface. The anal opening is sub-dorsal, about mm. above the posterior extremity of the body. There are ten tentacles with a disc diameter of 3 mm. and provided with retractile processes. 5 ambulacral papillae are situated on either side of the edge of the posterior half
. Echinodermata . Fig. 3. Calcareous deposits from Peniagone ferruginea n. sp. a—c from abactinal surface, d, e from actinal surface, /—// from the tentacles, /' from the tube-feet. The body is oval and about twice as long and one half as high as it is broad. The somewhat elongated mouth is situated on the anterior ventral surface. The anal opening is sub-dorsal, about mm. above the posterior extremity of the body. There are ten tentacles with a disc diameter of 3 mm. and provided with retractile processes. 5 ambulacral papillae are situated on either side of the edge of the posterior half of the body. The largest of these are mm. long and mm. broad. The hindmost papilla is situated at 2 mm. from the anus. The space between the papillae is to 3 mm. respectively. Besides these large ambulacral papillae there are three very small papillae directly below the anus. On the dorsal surface, at the base of the dorsal processes there are two small papillae on either side, mm. in length and mm. in diameter. The body-wall is very thin and, together with the ambulacral papillae and the tentacles, is abundantly fur- nished with calcareous deposits. The dorsal deposits are chiefly composed of spiny crosses with arms provided with small processes (fig. 3 a). These processes may frequently be as strongly developed as the branches which give the deposits a rather irregular shape (figs. 3 b, c). Simple, smooth, cruciform deposits and some peculiar saddle-formed ones may likewise be found, but they are rare. The deposits of the ventral surface are similar *
Size: 2231px × 2240px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectscienti, bookyear1921
