2g6 



The preceding observatioos justify my opinion that Aegeon affinis Alcock must at least 

 be considered as a distinct local variety of A. pennata (Bate). Aegeon obsoleta Balss seems indeed 

 to be identical with the typical species, because in the figure 3 of the original description (1. c.) 

 the posterior moiety of the lateral crest appears smooth and straight, not coarsely serrulate. 



In all the present specimens the deep vertical furrow is well-defined, by which, on either 

 side of the middle line of the 2 nd somite, the two tubercles are separated from one another : 

 in A. propensalata (Bate) these two tubercles are coalesced to a broad sinuous ridge. 



The two submedian carinae of the 6 th somite are armed in the ovigerous female with 5 

 retrorse sharp teeth, that gradually increase in length from before backward, in younger indivi- 

 duals there are only 4 or 3. 



Eggs very numerous, small, 0,8 mm. long, half as thick. 



Table of measurements in millimeters. 



Length of carapace, measured in the middle line . . . 

 Distance between the apices of the large hepatic spines. 



Length of abdomen. 



Width of 2 nd abdominal somite, looked at from above 



Entire length 



N° 1 and 2 larger male and larger ovigerous female from Stat. 306. 



Geographical distribution: Japan (near Enoshima, Dzushi, Sagami Bay) (Balss); 

 Arafura Sea (Bate); off the coast of Burma, Bengal and Madras (Kemp); Arabian Sea (Kemp); 

 off Bombay (Alcock) ; Persian Gulf (Kemp) ; Red Sea (Balss). 



2. Aegeon propensalata (Bate) var. hilarula de Man. PI. XXIV, Fig. 71 — 71/. 



Aegeon propensalata (Bate), var. hilarula J. G. de Man, in: Tijdschr. d. Ned. Dierk. Vereen. 

 (2) Dl. XVI, Afl. 2 and 3, 191S, p. 301. 



Confer also the following papers : 



Pontocaris propensalata C. Spence Bate, Report Challenger Macrura, 1S8S, p. 496, PI. XC, 



figs. 2, 3; PI. LXXXVI, fig. 5. 

 Pontocaris propensalata A. E. Ortmann, Proc. Acad. Nat. Sciences Philadelphia, 1895, p. 175. 

 Pontocaris media A. Alcock and A. R. S. Anderson, Annals Mag. Nat. History, April 1899, 



p. 282 (teste W. T. Calman). 

 Aegeon medium A. Alcock, A descript. Catalogue Indian Deep-Sea Crustacea, Calcutta, 1901, 



p. 120 (teste W. T. Calman). 

 Aegeon propensalata Stanley Kemp, in: Records Indian Museum, Vol. XII, Part VIII, Calcutta 



1916, p. 377. 

 Illustrations of the Zoology of the "Investigator", Plate XLI, figs. 6, 6a. 



Stat. 47. April 8/12. Bay of Bima, near south fort. 55 m. Bottom mud with patches of fine 

 coral sand. 1 male. 



Unfortunately the abdominal pleura of the typical Pontocaris propensalata have not 

 been described by Spence Bate. According to Dr. Calman, who was enabled to compare 

 co-types of Aegeon medium with the type of Bate's P. propensalata (Stanley Kemp, 1. c), 



