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MOLLUSCS. 



corded from the Atlantic coasts of North America, north coast of France, and some 

 parts of the Baltic. The animals belonging to the genus ScyUoea live upon floating 

 seaweed out on the high seas ; S. pelagica being usually found upon the gulfweed 

 of the Atlantic, which it resembles in its coloration. The foot is narrow, the sides 

 being thin, and capable of clasping the stems of the seaweed. The body is much 

 compressed laterally, and produced into two large leaf-like appendages on each side 

 of the back, on the inner surface of which the tufted branchial processes are situated ; 

 a median supra-caudal crest also bearing branchial filaments. The tentacles are 

 slender, laminated, and retractile within long compressed trumpet-shaped sheaths. 

 The genus contains only a few species, but it has been found in almost every sea. 

 Phyllirhoe is a genus of Nudibranchiata remarkable for the absence of both foot 

 and gills. The body is compressed laterally, and so translucent that all the internal 



Phyllirhoe bucephala in thl light, showing internal anatomy (greatly magnified). 



anatomy is visible. These animals are pelagic and eminently phosphorescent. 

 Specimens kept in aquaria have been observed to be instantly luminous if 

 touched. 



In the JEolidiidoB the body is slug-like and tapering posteriorly. There are two 

 labial and two dorsal tentacles, and the dorsal branchial papillae are cylindrical or 

 fusiform, and arranged in transverse rows on the sides of the back ; the front of the 

 creeping disc is often produced on each side in the form of tentacles ; the horny 

 jaws are large, and the radula consists generally of a single series of spinous plates. 

 jEolidia papillosa, the largest of the British species, may be found under stones 

 between tide-marks on many parts of the coasts. It is brown, grey, or orange, 

 spotted with brown or purple and white ; the dorsal tentacles are brown with 

 white tips, and the papillae are speckled with brown or lilac and white, with 

 white tips. These molluscs are animal-feeders, partial to sea-anemones. Their 

 fecundity is very great, as many as sixty thousand eggs being deposited by a 

 single individual at one time. These are enclosed in a perfectly transparent 



