1. '08. 166 



in only 80 to 90 fathoms (Goes, fide Ohlin), while Sars has re- 

 corded it from 30 fathoms off the Norwegian coast. The 

 species does not seem to have been hitherto caught in as much 

 as 775 fathoms. 



Tribe STENOPIDEA. 



Family STENOPIDAE. 



Genus Richardina) A. Milne-Mwards. 



Richardina spinicincta, A. Milne-Edwards. 



PL XXIII, figs. 1-10. 



Richardina spinicincta, A. Milne-Edwards, 1881. 

 Richardina spinicincta, A. Milne-Edw^ards, 1882. 

 Richardina spinicincta, A. Milne-Edwards, 1883, PI. 41. 



The rostrum is strongly compressed and about half as long 

 as the carapace measured in the mid-dorsal line. Dorsally it is 

 armed w^ith from nine to eleven evenly spaced teeth, behind 

 which a small blunt tubercle is usually found situated on the 

 carapace ; ventrally the rostrum is provided with from two to 

 five teeth on its distal half. The carapace is broad and only 

 slightly compressed ; at about its middle there is a prominent 

 transverse cincture of procumbent spines, about thirty in 

 number, which extends downwards on either side for rather 

 more than half its depth, an additional spine being present 

 in front of the most inferior of the series. Behind the base of 

 the rostrum there is a second transverse row of forwardly- 

 directed spines ; these are six or eight in number and are in- 

 terrupted in the mid-dorsal line by a carina which runs back- 

 wards from the rostrum, becoming obsolete shortly before it 

 reaches the posterior series of spines. The anterior margin 

 of the carapace is produced and rounded below the orbital 

 notch ; there is a small spine above the base of the antennae 

 and a number of spinules on the rounded inferior angle. 



The ahdominal somites are all smooth and evenly rounded 

 dorsally ; the first somite is not overlapped by the pleura of the 

 second. There is a minute spinule on the posterior margins 

 of the fourth and fifth somites above the acutely pointed in- 

 ferior angle, while on the proximal part of the sixth, near the 

 lower margin, there is a pair of stout spines. The telson (fig. 

 10) is about the same length as the inner and outer uropods and 

 is deeply sulcate in the mid-dorsal line, the convex portions 

 on either side being strongly spinose.^ There is a single very 

 strong lateral spine on either side at about the middle, and 



"I The arrangement of the dorsal spines seems to be subject to consider- 

 able variation. In fig. 10 (which illustrates the only perfect telson ob- 

 served) it will be noticed that they are not even placed eymmetrically. 



