T916.] vS. Kemp : Notes on Crustacea Decapoda. 375 



tocaris; the latter term should therefore lapse. Aegeon orientalis 

 agrees with Parapotitocaris in the complete absence of the hepatic 

 groove and in the arrangement of the carinae on the first and second 

 abdominal somites and resembles typical Aegeon in the very broad 

 antennal scale and in the possession of strong median spines on the 

 abdominal sterna. Aegeon habereri and lacazei are closely allied 

 forms ; in most respects they agree closely with typical species of 

 the genus, but they resemble Parapontocaris in the sculpture of the 

 first two abdominal somites and in the elongate form of the anten- 

 nal scale. 



In all six species of Aegeon are known from Indian waters; 

 they may be distinguished by the following key : — 



I. Second lateral carina of carap.ice interrupted anteri- 

 orly by a well defined hepatic groove; lateral parts of 

 ist and 2nd abdominal somites irregularly lobecl, with- 

 ciut sharp longitudinal keels continuous with those on 

 carapace. 



A. Median carina of carapace with 4 teeth ; two or 



three tubercles, forming an oblique transverse 

 row, between median and ist lateral carinae ... cafaphractits 



(Olivi). 



B. Median carina of carapace with 8 or g teeth or 



serrations ; surface between carinae of cara- 

 pace smooth, withotit tubercles. 



1. Marginal carina of carapace smooth ; 



two lobules separated by a \ertical fur- 

 row on either side of median carina of 

 2nd abdominal somite ... ... pcjuiata. Bate. 



2. Marginal carina of carapace serrulate; 



a sinuous longitudinal ridge, entire and 

 not divided by a furrow, on either side 

 of median carin.'i of ?nd abdominal 

 somite ... ... ... pi'opeiisalata, 



Bate. 

 II. Second lateral carina of carapace not interrupted, hep- 

 atic groove absent ; lateral parts of ist and 2nd ab- 

 dominal somites with sharp longitudinal keels conti- 

 nuous with those on carapace. 



A. 1st and 2nd lateral carinae of carapace with 



7 teeth, marginal with 7 to 9 ; antennal scale 



as broad as long ... ... .._ orientalis, 



Henderson. 



B. ist lateral carina of caiapace with 4 teeth, 2nd 



lateral with 3 to 6, marginal with 2 or 3 ; 

 antennal scale much longer than broad. 



1. 2nd lateral carina of carapace with 5 or 6 



teeth, marginal with 3 ; median carina 



of 2nd abdominal tergum bispinous ... aiidaDKniensc 



(\\'ood-Mason). 



2. 2nd lateral carina of carapace with 3 



teeth, marginal with 2 ; median carina 



of 2nd abdominal tergum unispinous ... heiigalense 



I Wood -Mason). 



Aegeon cataphractus (Olivi). 



1900. Aegean catuplwactus, Stebbing. Mmi/ie Invest. S. Africa, I, p. 50 



{^itbi syi!.'). 

 1905. Aj.egeon cataphractus, Pearson, Ceylo)i Pearl Oyster Fish., Macriira 



p. 89. 



