Elementary text-book of zoology, general part and special part: protozoa to insecta . elementarytextbo00clau Year: 1892 MABSUPIALIBA. 259 modified. As in Lucernariihe, the vasculai- spaces are wide pouches divided from each other by four narrow septa (figs. 198, 199). The nervous system is allied to that of the Hydromedusm by the presence of a sharply defined nerve-ring. This nerve-ring is placed on the sub-umbrella side of the bell, and, since at the bases of the four sense organs it lies further from the margin than it does at the corners of the bell, it has a sharply marked,
Elementary text-book of zoology, general part and special part: protozoa to insecta . elementarytextbo00clau Year: 1892 MABSUPIALIBA. 259 modified. As in Lucernariihe, the vasculai- spaces are wide pouches divided from each other by four narrow septa (figs. 198, 199). The nervous system is allied to that of the Hydromedusm by the presence of a sharply defined nerve-ring. This nerve-ring is placed on the sub-umbrella side of the bell, and, since at the bases of the four sense organs it lies further from the margin than it does at the corners of the bell, it has a sharply marked, zig-zag course. The nerve fibrilL-e given off from it mostly supply the muscular system of the sub-umbrella, and there give rise to numerous reticula of fibrillte connected with large ganglion cells. Large bundles of fibrillar com- parable to nerves have only been found in the four radii of the mar- ginal bodies. The latter attain a high degree of development, since the knob-like swelling in which they terminate possesses, in addition to the lithocyst, a complicated visual apparatus consisting of two large unpaired median eyes and four small paired latei-al eyes. The generative organs have a yeiy peculiar form. They are separated from the gastric filaments and as thin, rather broad plates attached in pairs to the four partition walls, reach the whole length of the Unfortunately knOwn of the Fie. 199.—The apicalhalf of a Charyldea divided transversely, seen from the sub-utnbrella side. The four oral arms are visible. Ov, Ovaries on the four septa, S; Ost, ostia of the gas- trie pouches; Gf, gastric filaments. vascular pouches, nothing is as yet development. Fam. Charybdeidae. Charyhdea mar- sypialis Per. Les. {Marsiijjialls Planci Le«.) Mediterranean. (3) Sub-order: Discophora {Acra- siieda), Ephyra-mednsce. Disc-shaped Acaleplia, the margin of whose disc is divided into eiyJct lobes. They have at least eight s'lh-marginal sense organs contained in niches, and vnth the sa
Size: 1361px × 1469px
Photo credit: © Bookend / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: archive, book, drawing, historical, history, illustration, image, page, picture, print, reference, vintage
