114 



STALK-EYED CRUSTACEA. 



and another pair of very long ones at the distal end ; the carpus is thrcc- 

 spined (one external proximal, two inferior distal) ; chela unarmed, fingers 

 crossed at tips. The next pair of appendages (second ambulatory) show a 

 merus armed with a long and slender spine at the distal end of the lower 

 side ; there is a minute spine at the corresponding place on the carpus ; the 

 chela is perfectly formed, but weak, the fingers not crossed. The next pair 

 (Plate XXX., Fig. V) are similar in form and armature to the second, but a 

 little shorter. The last pair of thoracic appendages (Plate XXX., Fig. I'') 

 are much smaller, reaching only to the end of the carpus of the antecedent 

 pair ; they bear no spines and end in an imperfectly formed chela, the pollex 

 consisting of a blunt process only one half as long as the index or dactylus, 

 which is long-haired on its external margin. 



The first pair of abdominal limbs (Plate XXX., Fig. V) are specialized to 

 serve as sexual organs (gonopods)^ they are similar in form to those oi Foly- 

 chelcs and WiUcmoesia, consisting of a basal stem and a terminal spatulate blade. 

 The second abdominal appendage (Plate XXX., Fig. 1'^) consists of a basal 

 stalk and two terminal branches ; near the base of the inner branch are two 

 long blunt processes (stylamblydes), the outer of which is longer than the 

 inner one. The third (Plate XXX., Fig. 1^), fourth, and fifth pairs of ab- 

 dominal appendages are similar in form to the second pair, but they are 

 furnished with only one stylamblys, which is longer than either of those 

 borne by the second pair. The sixth abdominal appendages (Plate XXIX., 

 Fig. 2^) are similar to those in the other genera of this family, and are equal 

 to the telson in length. 



The number and arrangement of the gills and epipods are exhibited in 

 detail in the subjoined table : 



Vl L 



Somites 



Pleurobranchiae 



ArthrobranchiEe 



Podobranchise 



Epipods 



VII. 





 

 



1 



VIII 





 

 

 



IX. 







1 







1 



X 





 2 

 1 

 



XI. 



1 



2 

 1 







XII. 



1 

 2 

 1 

 



XIII 



1 

 2 

 1 

 



XIT. 

 1 = 



= 











4 



9 



4 ■ 



:_^ (2) 



17 + (2) 



The arthrobranchia and the eplpod of the ninth somite are very small, 

 and the three gills appertaining to the tenth somite, although larger than the 

 gill borne on the ninth, are smaller than those on the following somites. 

 The epipods of the tenth to the thirteenth pairs of appendages arc repre- 

 sented merely by thin membranous expansions of the basal part of the 



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