98 DE. J. a. DE MAN ON THE PODOPHTHALMOUS 



frontal ridge, when examined under a lens. The convex ptery- 

 gostomian regions are slightly granular, and the inflected sides 

 of the cephalothorax are marked with some oblique elevated lines. 

 The outer surface of the ischium-joiiit of the external maxillipeds 

 presents an impressed longitudinal line, to which Mr. Hilgendorf 

 first directed attention as a character serving to distinguish the 

 species of this genus. In T. Callianira this line is situated about 

 the middle of the joint, and is directed a little obliquely, so that 

 it almost coincides with a diagonal uniting the internal angle of 

 the anterior margin of the joint with the external angle of the 

 posterior margin. The outer surface of this joint is minutely 

 punctate. In T. Jiydrodromus this impressed line is situated 

 much closer to the internal margin of the joint. 



The outer surface of the sternum and of the abdomen is faintly 

 punctate. The male abdomen has a characteristic form. It 

 gradually and rather rapidly narrows towards the posterior margin 

 of the penultimate joint ; the latter is nearly quadrate, and as long 

 as broad at the posterior margin, its lateral margins being nearly 

 straight. The terminal joint is distinctly longer than broad at 

 its base ; it is rounded at the tip, and the lateral margins are 

 slightly concave immediately behind the middle of the joint, 

 which therefore presents a characteristic form. In T. Jiydro- 

 dromus the penultimate joint is broader than long. 



T. Callianira belongs to the small species of the genus ; in the 

 adult ova-bearing female specimen the distance between the 

 epibranchial teeth measures only 15 millim. 



The anterior legs are very unequal, especially in the male ; and 

 the larger chelipede is found either on the right or on the left 

 side. The outer surface and the upper margin of the arm are 

 somewhat transversely rugose, and the anterior margin is some- 

 what granular. The upper surface of the wrist is slightly rugose 

 towards the external and internal margins ; the latter is armed 

 at the internal angle with an acute tooth. The larger hand is 

 about as long (the fingers included) as the breadth of the cephalo- 

 thorax, and twice as long as high (the fingers included). The 

 palm itself is but little longer than high at the base of the fingers ; 

 its outer surface is convex, smooth, and slightly punctate, like the 

 inner surface, and the upper and under margins are rounded. 

 The lower finger is slightly deflexed, and the mobile finger is 

 slightly arcuated, leaving a hiatus when closed ; both fingers are 



