10 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 123 



Color. — Largely faded in present material; bodies of some speci- 

 mens show traces of scattered black ckromatophores concentrated in 

 dorsal patches on sixth thoracic and first abdominal somites. 



Size.— Males, TL 20.9-23.8; females, TL ca. 10.0-30.1. Other 

 measurements of male, TL 20.9: carapace length 4.3; fifth abdominal 

 somite width 3.7; telson length 2.5, width 2.9. 



Discussion. — G. demanii is very similar to 6. hendersoni in general 

 appearance but differs in having rounded anterolateral angles on 

 the rostral plate, in having a few proximal setae on the inner margin 

 of the uropodal endopod, and in lacking the strong ventral carinae 

 on the submedian and intermediate marginal teeth of the telson. 



In general, the carinae of the telson of males are more tumid than 

 those of females, but dorsal tubercles of females are usually sharper. 



The number and arrangement of tubercles on the telson are quite 

 variable, but the posterior end of the median carina, the anchor, 

 and the dorsal surface of the other carinae are always armed. The 

 tubercles on the submedian teeth are usually arranged side-by-side, 

 rarely forming a triangle. On the intermediate teeth the tubercles 

 may be arranged in one or two longitudinal rows. 



The very small specimen from Hare Id. in the Gulf of Manaar 

 is tentatively assigned here. There are traces of one or two small, 

 proximal setae on the inner margin of the uropodal endopod, the 

 distal segment of the uropodal exopod is more rounded than in the 

 small specimen of G. hendersoni from Okinawa, and the ventral carinae 

 on the telson are very poorly developed. Further, the specimen 

 almost completely lacks the dorsal spinules of the telson. 



The illustrations of color pattern given by Gravier (1935) were 

 based on an outline drawing of G. chiragra (Fabricius). 



Distribution. — Western Indian Ocean, from localities between 

 India and Mozambique. Records include: Madras Harbor, India 

 (Kemp and Chopra, 1921); Rameswaram, Gulf of Mannar (Hender- 

 son, 1893; Thurston, 1895; Ingle, 1963); Paniban and Shingle Id., 

 Gulf of Mannar (Gravely, 1927); Bombay, India (Kemp, 1913); 

 Karachi, West Pakistan (Kemp, 1913); Astola Id., West Pakistan; 

 Persian Gulf (Nobili, 1906; Kemp, 1913); Arabian Sea (Kemp, 1913); 

 from scattered localities in the Red Sea (Nobili, 1906a; Tattersall, 

 1921; Kemp and Chopra, 1921; Maccagno, 1936; Ramadam, 1936; 

 Parisi, 1940; Holthuis, 1941; Stella, 1955; Ingle, 1963); Zanzibar 

 (Lenz, 1905, 1910; Nobili, 1905; Borradaile, 1907; Taramelli, 1955); 

 Aldabra Id. (Lenz, 1905, 1910); Ibo Archipelago (Kemp, 1913); and 

 from Fort Dauphin (Gravier, 1935) and Maromondia (Dollfus, 1938), 

 Malagasy Republic. 



