Carcinological Fauna of Inlia. 



237 



The external maxillipeds have the merus as wide as or much wider 

 than the ischium, and the palp inserted at the antero-intemal ano-le of 

 the merus. 



The rostrum is formed of two spines, which, may be horizontal, 

 semi-deflexed, or completely deflexed ; in the last case the spines are 

 usually more or less fused togethei\ 



The ambulatory legs are of no great length. 



Key to the Indian genera. 

 fl. Supra-ocular fi. The antennwlary 



Alliance 1. Maioid- 

 a. — C arapa c e 

 either regularly 

 pyriform or sub- 

 circular : rostral 

 spines horizontal: 

 orbits incomplete 

 below ; but fairly 

 well roofed in 

 above (1) by a su- , 

 pra-ocular eave, ' 

 which has at least 

 its postero-exter- 

 nal angle pro- 

 duced, (2) by a 

 post-ocular spine, 

 and (3) by a spine 

 intercalated 

 between (1) and 

 (2). 



eave and interme 

 diate spine very 

 prominent : eye- 

 stalks slender and J 

 curved, with the ' 

 cornea elongate 

 and occupying a 

 positionmore ven- 

 tral than terminal. 



flagelluni springs, 

 or appears to 

 spring, from with- 

 in the orbit Maia. 



h 



ii. The autennffiary 

 flagellum arises 

 quite clear of the 

 orbit 



2 



Paramithrax. 

 [Chlorinoides.] 



. S u p r a - o c u 1 a r 

 eave and interme- 

 diate spine dis- 

 tinct, but not very 

 prominent: eye- 

 stalks stout, with<{ 

 rounded corneae 

 which occupy a 

 position as much 

 terminal as ven- 

 tral. 



fi. Carapace pyri- 

 form : rostral 

 spines of consider- 

 able length, and 

 with one or more 

 accessory spines 

 on the outer sur- 

 face Schizophrys. 





I 



ii. Carapace subcir- 

 cular : rostral 

 spines simple, and 

 so short as to 

 hardly break the 

 general outline of 

 c the carapace Cyclax. 



2-V-") 



semi-tubular antlers followed 

 by a long isolated post-ocular 

 tooth : rostrum vertically 

 deflexed : buccal frame much 

 broader in front than behind. 



Alliance 2. Stenocionopoida. fl. Orbits in the form of huge 

 — Carapace pyriform, often 

 broadened anteriorly : the 

 orbits either have the form 

 of long semitubular antlers 

 which sheathe the eye-stalk, 

 but do not protect the eye, 

 the cornea in retraction being 

 protected by the base of an 

 extremely long and promi-^ 

 nent, isolated, post-ocular 

 horn ; or are reduced to the 

 form of long outstanding 

 horns similar to those of the 

 rostrum : eye-stalks extreme- 

 ly long: the external maxilli- 

 peds have the external angle 

 much produced : the rostrum 

 consists of two long horns. (. 



83 



Criocarcinus. 



*v 



2. Orbits in the form of long 

 outstanding horns similar to 

 those of the rostrum, which 

 is not deflexed, buccal frame 

 quadrangular Stenocionops. 





