398 ECHINODERMS OF THE BRITISH I8LES 



1. Cucumaria frondosa (GunneruH) . (Fig. 236.) 



(Syn. Holoihuria frondosa Gunn. ; H. j^entades O. Fr. Miill. ; 

 H. fucicola Forbes and Goodsir ; (?) Psolinus brevis Forbes.) 



Body cylindrical, somewhat attenuating towards the ends ; 

 tube-feet in larger specimens pluriseriate, especially in the middle 

 of the body, spreading to some degree also over the interradii on 

 the dorsal side. They are completely retractile. Skin very thick, 

 leathery, in larger specimens almost completely devoid of 

 calcareous deposits ; young specimens with a variable number of 

 larger fenestrated plates with a few small tubercles (Fig. 239, 2), 

 Colour dark brownish, somewhat lighter on the ventral side ; 



Fig. 236. — Cucumaria frondosa. Much reduced. 



tentacles almost black. More lightly coloured specimens may 

 occur, even such as are quite white. Grows to a very consider- 

 able size, up to ca. J metre fully extended. 



This large sea-cucumber, the largest of British and European 

 species, is often found in great numbers at lower tide limit, 

 especially among Laminarians, and, with its long extended bush- 

 shaped tentacles, offers a very fine sight. Large specimens are 

 difficult to preserve in extended condition ; if preserved without 

 narcotising they contract very strongly, pushing out their internal 

 organs through the anus or through a rupture in the skin, usually 

 in the anterior part of the body, where the skin is somewhat 

 thinner. 



Breeding season February-March, farther to the north 

 (Greenland) in summer-time. The red, barrel-shaped larvae may 

 occur in such great numbers that the water looks quite red from 



