244 Records of the Indian Museum. [Vol. XXIV, 



1729/7, 2| miles E.S.E. of Santa- ' Investigator,' Feb., One $ , 



pilli Lt., near Vizagapa- 1890. Type. 



tarn, Madras Coast, 15- 



17 fms. 

 C 406/1. 3 miles* E.S.E. of Kabusa ' Investigator,' Oct., One 6 , 



Is., Mergui, i2°44'3o" 1913- Type. 



N., 97 55'3°" E -. 35 fms. 



Alcock's notes refer to the female obtained at the first of these 

 localities. The labels of the male do not indicate that it was found 

 in any particular association. 



Genus Thaumastocaris, nov. 



Rostrum well developed, laterally compressed, with large 

 teeth. Carapace laterally compressed, not sculptured. Basal seg- 

 ment of antennule broad; antennal scale well developed. Man- 

 dible without palp; inner lacinia of maxillula narrow; all maxilli- 

 peds with exopods, the second without podobranch, the third slen- 

 der. Carpus of first peraeopods divided into a number of subseg- 

 ments. I^ast three peraeopods with dactylus biunguiculate, but 

 without basal process. Pleura of abdominal somites rounded in- 

 teriorly. 



Type and only known species, — Thaumastocaris streptopns, 

 sp. nov. 



This genus is proposed for a Pontoniine prawn from New Cale- 

 donia belonging to the Paris Museum which is remarkable for the 

 fact that the carpus of the first pair of peraeopods is divided into 

 a number of subsegments. _ In this curious feature it differs, I 

 believe, from all Macrura hitherto known. 



The carpus of the second peraeopod is frequently segmented 

 in Caridea and the character is of value in distinguishing certain 

 of the families into which the tribe is divided. Much less signi- 

 ficance is, however, to be attributed to the occurrence of the same 

 feature in the first peraeopod of Thaumastocaris, for it is by this 

 feature alone that it can be distinguished from Periclimenes. In 

 Thaumastocaris the hepatic spine is absent and the dactylus of the 

 last three legs biunguiculate. In these points it resembles Peri- 

 climenaeus and I have no doubt that it is in this subgenus or in 

 the closely related Periclimenes s.s. that it finds its nearest allies. 

 It is not easy to decide how much importance should be attributed 

 to a unique character such as that on which this genus is founded ; 

 it is possible that its affinities would be more clearly shown by 

 regarding it merely as a subgenus of Periclimenes. 



Thaumastocaris streptopus, sp. nov. 



The rostrum (text-fig. 78) reaches to the end of the antennal 

 scale and is deep in lateral view. The upper border is straight and 

 in the single specimen examined bears a series of 10 closely set teeth 

 which increase in size from behind forwards and are all very large ; 

 the three posterior teeth are situated on the carapace behind the 



