422 



ECHIN0DERM8 OF THE BRITISH ISLES 



excentrica Herouard ; Tr. grossularia Herouard),* Bay of Biscay 

 to Senegal, 2779-5000 m. (" Talisman ", " Princesse Alice "), 

 elsewhere known from the West Indies, 1720 m. (" Blake ") ; 

 M. loricata (Perrier) (Syn. Ankyroderma loricatum Perrier), off 

 Portugal to Cape Verde, 1090-2324 m. (" Talisman ", '' Princesse 

 Alice") ; M. maroccana (Perrier) (Syn. Ankyroderma maroccanum 

 Perr.), 30° 9' N., 14° 1' W., 2210 m. (" Talisman ") ; M. musculus 



Fig. 257. — Calcareous deposits of Molpadids. (1. After Danielssen and 

 Keren, Holoth. Norweg. N. Atl. Exp. 2-6. After Perrier, ''Talisman" 

 Holoth.) 

 1. Anchor and anchor plates of Molpadia ooUtica. 2. Deposit of M. albicans. 3. De- 

 posits of 31. blakei ; siile view and from above. 4-5. Smaller and larger plate of M. maroc- 

 cana. 6. Fusiform deposit from il/. OTUsctiZus. 1. xca. 35; 2 and 6, xca. 100; 3, ca. 135; 

 4-5, xca. 45. 



Risso (Syn. Haplodactyla mediterranea Grube, Ankyroderma 

 musculus (Risso), A. Perrieri Petit, A. hispanicum Petit, A. 

 Danielsseni Theel, Trochostoma violaceum Theel), from off Portugal 

 and the Canaries, 106-1139 m. (" Talisman "), elsewhere found in 

 the Mediterranean, off the east coast of N. America, the Antarctic 

 and Indo-Pacific Seas, thus rather cosmopoUtan ; M. oolitica 

 (Pourtales) (Syn. Molpadia borealis Sars ; Trochostoma Thomsoni 



1 The only character distinguishing the var. excentrica and Tr. grossularia 

 from M. blakei appears to be the eccentric position of the tail, which may 

 perhaps be due to contraction on preservation ; as, moreover, it is not 

 Icnown whether or not the tail of the typical blakei is likewise eccentric, 

 there is, for the present at least, no reason for maintaining these forms as 

 separate from M. blakei. 



