246 



Records of the Indian Museum. [Vol. XXIV, 



The distal endite of the maxilla, as in most Pontoniinae, is 

 divided into two lobes. The third maxilliped extends to the 

 middle of the second antennular segment and is slender. It 

 possesses a small arthrobranch and the exopod does not reach 

 the distal end of the antepenultimate segment. The ultimate 

 segment is less than two-thirds as long as the penultimate. 



The first peraeopods (text-fig. 80a) are very long and slender : 

 the mero-carpal articulation reaches to the end of the basal anten- 

 nular segment. The merus is about 14 times as long as wide and 

 is divided by a rather obscure articulation into two subsegments, 

 the distal about two-thirds the length of the proximal. The car- 



Text-fig. 80. — Thanmastocaris streptopus, sp. now 



First peraeopod. ■ c. Fingers of second peraeopod. 



Second peraeopod. d. Third peraeopod 



e. Dactyl us cf same. 



pus is very slender, about r.35 times as long as the merus and 36 

 times as long as the chela. It is divided by transverse or oblique 

 articulations into six subsegments, the order of which, when 

 arranged according to length is 1, 6, 3, 2, 4, 5. The first subseg- 

 ment is twice as long as the sixth, the second, third and fourth are 

 subequal and the fifth, which is the shortest, is about 25 times 

 as long as wide. The chela is slender, with fingers unarmed and 

 little more than half the length of the palm. 



J udging from the size of the basal segments the second peraeo- 

 pods do not differ greatly in size, but only the left limb (text-fig. 

 806) is present in the unique specimen. It extends beyond the 



