374 



ECHINODERMS OF THE BRITISH ISLES 



of the Canaries, 860-2200 m. ("Talisman") ; and B. typica 

 Theel (Fig. 215), from off Spain, the Canaries, and the Azores, in 

 depths of ca. 2000-3825 m. 



Key to the N.E. Atlantic species of Benthodytes. 



1. Tentacles 20. Marginal web broad. Deposits simple, spinous 



rods, often absent ....... 2 



Tentacles 14-15. Marginal web narrow. Deposits 4 -armed, 

 spinous rods ........ 3 



2. About 8 small, retractile papillae in each dorsal ambulacrum 



(" Challenger " Holoth., p. 103, PI. XXVII. 7) B. typica Theel 

 No dorsal papillae C Talisman'' Holoth., p. 462, Pis. XIII. 5, 



XX. 31) . . . . . . B. glutinosa Her. 



3. Dorsal side very vaulted, with 4 pairs of large, conical appendages 



and a variable number of small. Deposits slender. Colour 

 violet. (" Monaco ", vi., p. 10, Pis. I. 3, II. 4) 



B. janthina v. Marenz. 



Dorsal side not very vaulted, with 3 pairs of large, whip-like 



papillae and a variable nimiber of small. Deposits stout, outer 



projection often divided into 2-3 strong branches. Colour 



white to reddish (" Talisman'' Holoth., p. 456, Pis. XII. 1-2, 



XXI. 1-9) B. lingua Perr. 



Euphronides Theel. (Fig. 222.) 

 (Syn. Triconus Herouard.) 



Body more or less depressed, especially anteriorly. Skin 

 gelatinous. Mouth and anus ventral. Tentacles 10-18, increas- 



FiG. 222. — Euphronides cornuta, dorsal side ; the anterior end is to the right. 

 Reduced. (After Verrill, " Albatross " Rep.) 



ing in number with age. Dorsal side anteriorly with 4-6 pairs 

 of papillae, the posterior ones the largest. Dorsal unpaired 

 appendage not very long, usually a considerable distance from 

 the posterior end. Mid-ventral radius with a double row of 

 tube-feet ; lateral tube-feet small and numerous, forming a con- 

 tinuous narrow marginal fringe. Deposits cross-shaped bodies, 

 those of the ventral much smaller than those of the dorsal side. 



