^y8 Records of the Indian Musewn. [Vol. XII, 



i8yo. Poiitocaris mcifici, Alcock and .XndL'fson, .lini. Mug. Xaf. Hist. 

 (7), III, p. 282. 



1900. Poiitocaris propensalafa. Whiieleiige, Mem. Aiisfni/ian Miis.. \\ . 



p. 198. 



1901. Aegeoi/ inediiiiii, Alcock, Cat. Indian deep-sea Crust. Macriira and 



Anouiala, p. 120, and I/lust. Zool, ' Investigator,' pi. xli, Hg. 6. 



In this case also I am indebted to Dr. Caiman for the elucida- 

 tion of the synonymy. Dr. Caiman has kindly compared co-t3'pes 

 of A. medium with the type of Bate's P. propensalata and has sent 

 me the following note on the subject. — " 1 cannot find any differ- 

 ence between the type of P. propensalata and A. medium. The 

 sculpturing of the abdominal somites is less sharp in the former 

 and the serration of the supramarginal carina of the carapace is 

 very obscure — as it tends to be in the smaller of the two speci- 

 mens of A. medium that I have examined." 



The only specimens in the Indian Museum are those described 

 by Alcock from the Andaman Sea, 55-66 fathoms. Bate's type 

 specimen was obtained off the Ki Is., south of New Guinea, 5°49' 

 15" S., 132° 14' 15" E., at a depth of 140 fathoms, and Whitelegge 

 has recorded the species from 50 fathoms in Botany Bay. 



Aegeon orientalis, Henderson. 



1893. Aegean orientalis, Henderson, Trans. Linu . Sac , Zool. (2), V, p. 446, 

 pi. xl, figs. 16, 17. 



Three specimens in rather poor condition from the Persian 

 Gulf and the Andamans evidently belong to this species, which 

 does not appear to have been recognised since it was first described 

 more than twenty years ago. 



The spinulation of the carapace agrees exactl}^ with Hender- 

 son's description except that the serrations on the marginal carina 

 vary in number from 7 to 9. The abdominal sculpture also agrees 

 with the original description ; but there are two longitudinal carinae 

 on either side of the second abdominal somite, and the five carinae 

 on the first somite, as well as the median carina on the second, end 

 anteriorly in sharp spines. These spines were perhaps worn away 

 in the type, which is larger than any of the three specimens here 

 recorded. 



Although, as Henderson has remarked, the species bears a 

 rather marked resemblance to A. caiaphr actus, it is not in reality 

 a very close ally of that species. As has already been pointed out 

 it is intermediate in character between the more typical species 

 and those that Alcock referred to the subgenus Parapontocaris. 

 Pearson's suggestion that A. orientalis is merely an extreme -v^iri^t.- 

 tion oi A . cataphractus ^ is certainly incorrect. A. orientalis may 

 readily be distinguished (i) by the complete absence of the hepatic 

 groove, (ii) by the smaller number of serrations on the marginal 

 carina of the carapace, (iii) by the sharp longitudinal lateral carinae 

 of the first two abdominal somites and (iv) b}^ the presence of only a 



' Pearson, Ceylon Pearl Oyster Fisheries, Macriira, p. 89 (1905). 



