26 CARCINOLÜGICAL STUDIES 



Gelas. tetrogonon Herbst is disüibuted from the Red 

 Sea and Zanzibar to the Sandwich Islands, Tahiti and 

 Sydney (Hess). 



10. G e I a s im u s Dussumieri M. E. 



Gelasimus Dussumieri ., H. Milne Edwards, in: Annales des Scien- 

 ces Naturelles, T. XYIII , 4852, p. 148, PI. IV, fig. 12. 



Gelasimus Duss-xmieri, de Man, in: Journal Linnean Soc. of Lon- 

 don, Vol. XXII, 1888, p. 108, PI. VII, fig. 2—7. 



The Leyden Collection contains five male specimens from 

 Java, some of which are adult, a male from the Island 

 of Nossy-Faly near Madagascar, a large number of rather 

 young specimens, both males and females , from Amboina , 

 and two male specimens from the Island of Ponape , pur- 

 chased from the Museum Godeffroy. I have given a complete 

 description of this common Indian species in my » Report 

 on the Crustacea of the Mergui Archipelago", so that I 

 will only add the following remarks. 



In the specimen from Nossy-Paly the immobile finger 

 of the larger hand is rudimentary ; this hand has been 

 figured by Hoffmann (Crustacés de Madagascar, 1874, PI. 

 HI, fig. 22). 



In a few male specimens of those collected at Amboina 

 and which are all very young , I observe a trace of an 

 accessory row of granules on the walls of the 

 orbits near the inferior margin. This fact is of 

 some importance as there is usually in this species n o 

 trace of that accessory row. But as the cephalothorax 

 of these individuals has exactly the same form as that of 

 the other specimens, being quite as long in proportion to 

 the distance between the external orbital angles, and as 

 they have been collected in the same locality , they are 

 without any doubt to be referred to the same species. 



It is not easy to indicate the diff'erences by which Gelas. 

 Dussumieri may be distinguished from the Japanese Gelas. 

 arcuatus de Haan. The lateral margins of the cephalotho- 



Notes from the Leyden Museum , Vol. XUI. 



