44 CARCINOLOGfCAL STUDIES. 



thorax being dark green, the larger hand of a beautiful red, the 

 fingers of a paler colour and the ambulatory legs reddish brown. 



This species has been observed at Mauritius and seems 

 to be very rare. 



The two specimens were labelled » G«/as. Za/m//w, Nou- 

 velle Calédonie" ; but this label not being applicable to these 

 specimens, and Milne Edwards not quoting Gelas. chloro- 

 phthalmus amongst the species of New Caledonia, the locality 

 where our specimens have been collected , remains uncertain. 



20. Gelasimus inversus Hoffm. 

 (PI. 4, fig. 12). 



Gelasimus inversus, Hoffmann, Criistacés de Madagascar et de 

 rile de la Reunion, 1874, p. 19, PI. IV, fig. 23—26. 



Gelasimus chlorophthalmus, Hilgendorf, in : Monatsberichte konigl. 

 Akad. der Wissensch. zu Berlin, 1878, p. 803. 



Three of the four original specimens of this species, 

 which were described by Hoffmann , exist still in the Leyden 

 Museum , unfortunately in a very bad and mutilated state. 

 They have been collected on the Island of Nossy-Faly , 

 where their indigenous name is »Cava tangena". 



There can be little doubt that the specimens referred to 

 Gelas. chlorophthahnus by Hilgendorf belong to Gelas. inver- 

 sus, and Hilgendorf, apparently, was not acquainted with 

 Hoffmann's description. As this latter is rather complete, 

 I will only compare the species with its nearest ally, viz. 

 Gelas. lacteus de Haan. 



The lateral margins of the cephalothorax are a little 

 more oblique than those of the species of de Haan, in 

 which the antero-lateral margius are directed forward and 

 scarcely outward. As to the structure of the upper orbital 

 margin, both forms fully agree with one another, the 

 inferior of the two lines which constitute this margin, 

 being very indistinct and scarcely separated from the upper 

 line. The lower margin of the orbits of Gelas. lacteus appears 

 slightly convex , when the cephalothorax is seen from above, 



Notes from, the Leyden ]VIuseu.m, Vol. iX.111. 



