82 ECHINODERMS OF THE BRITISH ISLES 



it probably has direct development, without a pelagic larval 

 stage. Nothing is known about its food. It may be found on all 

 sorts of bottom. 



In the British seas this species has been recorded from the 

 Faroe Channel, 440 fms. (" Porcupine "), from the Lousy Bank, 

 and from 50 miles W.N.W. of Eagle Island, N. Mayo, 388 fms. 

 (•' Helga "). Elsewhere it has a very wide distribution ; on the 

 Scandinavian coasts it occurs from Finmark to Skagerrack ; it is 

 further recorded from off Morocco and the Azores, and from 

 Greenland down to 41° N. on the American coast. The bathy- 

 metrical distribution is ca. 20-1400 m. 



2. Ceramaster halteatus (Sladen). (Fig. 45.) 



(Syn. Pentagonaster Gosselini Perrier ; (?) P. hystricis v. Marenz. ; 

 (?) P. Kergroheni Koehler ; (?) P. hcesitans Perrier.) 



Body less distinctly pentagonal, arms more distinct and inter- 

 radii forming a more pronounced arch than in the preceding 

 species. Marginal plates wholly covered with granules. Adam- 

 bulacral plates with 5-4 furrow spines, and outside these a series 



of mostly three club-shaped spines 

 and some outer spines which are 

 quite similar to those of the in- 

 terradial plates. Small pedicellarise 

 may occur, mainly on the marginal 

 plates. Il = ca. l-8r. Not known 

 to grow to a larger size than 44 mm. 

 diameter. Colour in life light 

 yellowish -red. 



Development and biology un- 



FiG. 45. — Ceramaster halteatus, ^^own. 



dorsal side. Nat. size. (After In British seas this species has 



Sladen, Echinod. S.W. Ire- ^^^^ ^^^^^ ^j^j^ ^^ g ;^ Ireland 



in 750-795 fms. (Green, " Helga "). 

 It is further known from the Azores and the Cape Verde Islands, 

 946-1770 m. 



It seems not improbable that this species is identical with 

 the Mediterranean species Ceramaster {Pentagonaster) hystricis 

 (v. Marenzeller), with which again the species Kergroheni Koehler 

 from the Bay of Biscay appears to be identical, the character 

 especially distinguishing the latter : a naked space on the distal 

 upper marginals, also being found in larger specimens of the 

 Mediterranean C. hystrix. It is not yet known whether such 



