440 



356 



Fig. 191. Primno latreillei Stebbing (after Bowman, 1978). 



Actually, in the cold-water regions the period of maturation of the 

 crustaceans could be protracted and before achieving full maturity, they 

 might undergo several more molts to reach much larger sizes (the number 

 of segments in the rami of the pleopods in the illustration of P. macropa 

 by Bowman is more than in P. latreillei, which confirms the greater 

 number of molts through which the former species passed). Further, 

 with an increase in number of molts, additional denticles could appear in 

 the basal part of the subchela of pereopods V. Generally, ornamentation 

 with denticles, spines, and setae in hyperiids is subject to wide variation. 

 This applies also to the ornamentation of the posterior margin of the 6th 

 segment of pereopods VI with small setae; this is "very distinctly seen" 

 in P. macropa while in P. latreillei this margin is "distinctly smooth, 

 the smallest setae seen only under high magnification" (Bowman, 1978). 



