Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 STELLERIDEA. 293 situate inter-radially and upon the dorsal surface. The multilobed branched diverticula of the stomach extend into the cavities of the arms (fig. 218). On the ventral sin-face of the latter, two or four rows of ambulacral feet project from the deep ambulacral groove, the edge of which is beset with papilla? (fig. 235). Pedicdlarice are also found, and dermal gills projecting through the tentacular pores of the dorsal surface. They feed principally upon Mottusca, and, by
Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 STELLERIDEA. 293 situate inter-radially and upon the dorsal surface. The multilobed branched diverticula of the stomach extend into the cavities of the arms (fig. 218). On the ventral sin-face of the latter, two or four rows of ambulacral feet project from the deep ambulacral groove, the edge of which is beset with papilla? (fig. 235). Pedicdlarice are also found, and dermal gills projecting through the tentacular pores of the dorsal surface. They feed principally upon Mottusca, and, by means of their ambulacral feet, crawl slowly upon the bottom of the sea. Some few of them are developed by a very simple process of metamorphosis within the brood-pouch of the mother: but the greater number of them pass through the free larval stages of Bipinna/ria and Brachiolaria (figs. 224 and 228). Fam. Asteriadae. The- cylin- drical ambulacral feet end in broad suctorial discs, and are usually arranged in four rows along each ambulacral groove. Astcriax L. (AgteracantTiiori), A. fflacialia 0. F. Miiller., Ile- lia»trr lirJianthnx Gray. Fam. Solasteridse. The cylin- drical ambulacral feet are dis- posed in two rows. Rays long, often more than rive Snltixfrr j)ft2)poxn>i Retz., sepositias Retz., Ophidiagt&r Ag., Linckia Nardo. Fam. Astropectinidae. Am- bulacral feet conical, and with- out suctorial disc, arranged in two rows. There is no anus. aiirtintiiicnx Thil. Lmditi CtenmUxrits Miill. Tr. Fam. Brisingidae. l>udy shaped like an Ophiurid. Rays distinct from the disc with only a narrow internal cavity. Jirixini/a comnntti Sars. FIG. 237.—Asteriscu* verrnculatus, with the dorsal skin removed. Ld, Ralial appendages or hepatic tubes of the stomach ; G, generative glands. Axtropectcn, Sub-Class 2.—OPHIURIDEA (Brittle Stars'). Asteroidea characterised by the absence of an anus, and by the pos- session of Ion;/ cylindrical arms which are sharpf-
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