CRUSTACEA — WHITELKGGE. 



226 



C A L A T H U K A , Norman and Stebbiiiy. 

 CALATHUllA GIGAS, sp. nov. 



(Figs. Vda-e.) 



Htation 34. 



Body moderately stout, elongate. Cephalon a little broader 

 than long; front bisinuate with a short, median rostriform pro- 

 cess; the antero-lateral angles are 

 rounded and project on each side so as 

 to embrace the outer bases of both 

 pairs of antennae; sides rounded, faintly 

 concave about the middle. 



First peraeon segment closely united 

 to the cephalon ; it exceeds the latter 

 in breadth and is twice as long ; the 

 anterior margin is straight, the sides 

 concave, laterally arched, and some- 

 what angular, especially anteriorly. 



Second to sixth segments agreeing 

 closely with the same segments in 

 Calathura brachiata, Stimpson, the 

 median depressions being, perhaps, a 

 little less marked. 



Seventh segment broader than long, 

 with a prominent lobe on each postero- 

 lateral angle. The lobes extend over and beyond the first 

 segment of the pleon. 



Superior surface of cephalon and first three segments of peraeon 

 more or less convex, succeeding segments somewhat flattened. 

 Inferior surface of first peraeon segment with a blunt longitudinal 

 keel, the second strongly but roundly convex; the five segments 

 following have the lower surface flattened; the sides are defined 

 by a distinct ridge; mesially there is a narrow longitudinal 

 groove which marks the inner limits of a series of transverse 

 corrugations; the latter are much more distinct in the male than 

 in the female. 



Pleon less than twice as long as the last segment of the peraeon. 

 Segments well defined, becoming wider posteriorly; first longer 

 than the second, third and fourth, but shorter than the fifth. 

 Lateral margins obliquely truncated, rather pointed posteriorly. 



First pair of pleopods nearly equal in length to the pleon and 

 telson combined; the outer ramus is narrow, oblong and becomes 



Frontal Region. 

 Fig. 19a. 



