26 G-- O. Sars. 



The enclosed animal (see fig. 3) exhibits the same prin- 

 cipal parts as in the female, and on the whole of a rather 

 similar structure. On a closer examination, however, some 

 well-marked differences are to be found. 



Thus the head (fig. 4) looks rather unlike owing to the much 

 fuller development of the rostral expansion. Whereas in the 

 female this expansion is very short and obtuse, it has here 

 the form of a strongly prominent triangular lamella, pointing 

 straight downwards, and terminating in an obtuse point. The 

 notch defining the expansion from the frontal part, is also 

 more conspicuous, though obtusangular. 



The antennulæ (see fig. 4) appear somewhat larger than 

 in the female, and have a greater number of papilligerous 

 expansions on the anterior edge. 



The antennæ and oral parts, on the other hand, are ex- 

 actly of same structure as in the female. 



Of legs, there is one pair more than in the female, viz., 18 

 pairs in all. The 2 anterior pairs (see fig. 3) are peculiarly 

 modified, being transformed into strong grasping organs, by the 

 aid of which the male gets hold of the female during copulation. 

 They are almost exactly alike both in size and structure, both 

 pairs having (see fig. 5) the 3 proximal endites almost obsolete, 

 and terminating with a rather broad and complex, forcipate hand. 

 The latter will be found, by comparison, to constitute the 

 transformed terminal part of the stem, comprising the 2 outer 

 segments together with the corresponding endites, the claw, 

 or dactylus, being the transformed 5th endite, whereas the 

 thumb is formed by the 4th endite. The hand (fig. 6) is in 

 both pairs considerably broader than it is long, and has inside, 

 a short triangular projection, below which the thumb is seen 

 to project. The latter is of a short cylindric form and densely 

 clothed on the obtusely rounded tip with curved spines and 

 fine bristles; moreover it carries a small setiferous lobe curv- 

 ing downwards. The claw is extremely strong, chitinous, and 



