404 ECHINODERMS OF THE BRITISH ISLES 



five ambulacra, retractile. Deposits very numerous, button-like, 

 covered with nodules ; they are usually somewhat larger and with 

 more holes than in those of C./ac^ea, which they otherwise resemble 

 very much, as also the small, irregular " cups " in the outermost 

 layer of the skin are identical in the two species. Colour brownish, 

 often with irregular darker spots. Grows to a size of ca. 15 cm. 

 length, by a thickness of 3-3-5 cm. 



Development direct, without a pelagic larval stage. It prefers 

 a muddy bottom, in depths of a few metres. In the Mediter- 

 ranean the fishermen use it (the inner layer of the skin) for bait. 



In British seas this species has been recorded from the south 

 coast to the Clyde. It is elsewhere known from the coast of 

 Portugal, off Senegal, and the Mediterranean. Bathymetrical 

 distribution ca. 15-175 m. 



2. Echinocucumis M. Sars. 



Body thick, ovoid, attenuating at both ends, which curve 

 upwards, the mouth and anus being thus dorsal. The body wall 

 is thin, but stiff on account of the large, scale-like deposits, which 

 carry a rather long spire, making the body spinous. Tentacles 

 unequal, a lateral pair much larger than the others ; the ventral 

 tentacles small, rudimentary. Tube-feet scarce, very thin, not 

 perforating the scales, but issuing between them, at most forming 

 a notch in the edge of the scales. These latter are thin, single - 

 layered ; the spire eccentric. Small forms, mainly from deeper 

 water. 



Only one species known from the British and N.E. Atlantic 

 seas. 



1. Echinocucumis hispida (Barrett). (Fig. 242.) 



(Syn. Eupyrgus hispidus Barrett ; Cucumaria hispida Bell ; 

 Echinocucumis typica M. Sars ; Ypsilothuria talismani Perr., 

 pro parte.) 



Anterior and posterior end forming long, slender tubes, which 

 cannot be completely retracted. Tube-feet in the ventral radii 

 in zig-zag rows ; in the dorsal radii they are found only at the 

 anterior and posterior end, not in the middle of the body. They 

 are rather difficult to see, being scarcely larger than the spines. 

 Scales large, more than 1 mm., smooth, perforated by rather 

 large holes, becoming smaller towards the margin (Fig. 243). 

 Most of the plates carry an eccentric spire, composed of 4 

 slightly spiny rods. Towards both ends the spire disappears 



