ECHINOIDEA 



337 



but is not known from Iceland, Greenland, or the east coast of 

 N. America. Bathymetrical distribution, 0-ca. 260 m. 



3. Brissopsis L. Agassiz. 



Besides the subanal fasciole a peripetalous fasciole is present, 

 encircling the whole of the widened ambulacra (petals) on the 

 upper side. Frontal ambulacrum more or less deepened. Four 

 genital pores. Forms of moderate size, with rather fragile test. 



Only one species known from the British seas, but a second 

 species, Brissopsis atlantica Mrtsn., may be expected to occur 



12 3 4 



Fig. 199. — Globiferous pedicellaria of Brissoj^sis lyrifera (1) ; slender form 

 of globiferous pedicellaria of Briss. atlantica (2) ; rostrate pedicellaria 

 of Briss. lyrifera (3) ; 8-valved pedicellaria of Briss. atlantica (4). 

 1, xl6; 2, x35; 3, x 30 ; 4, x 40. (After Th. Mortensen, " /w^o// " 

 Ech., ii.) 



in the deep sea off the west coasts, this species having been found 

 at 37° 52' N., 9° 15' 45" W., 552 m. (" Princesse Alice "), and 

 also in the Mediterranean ; it is found elsewhere off the east coast 

 of N. America and in the West Indies, in depths of ca. 125-2440 m. 

 The Mediterranean form has been distinguished as a separate 

 variety, Var. mediterranea Mrtsn. ^ 



1 For a full description and figures of Brissopsis atlantica see Th. 

 Mortensen, '' Ingolf Echinoidea, ii., p. 160, and the same author's Die 

 Echiniden d. Mittelmeeres, p. 29. 



