APPENDIX— CUUHrAGEA. 123 



rather shorter, and the fingers are straighter. Tlie ambulatory legs (which 

 are imperfect) are of moderate length, and Imt slightly compressed, and 

 naked, the dactyli styliform slightly longer than the penultimate joints, nearly 

 straight, and armed with rather distant spinules. 



In the specimens from Milligalli tlie iiunctulations of the carapace are 

 much more distinct and numerous, the granulated post-frontal ridge is 

 obsolete, and the eyes more nearly fill the orbital cavities (see Fig. B). In 

 the single example from Tumbaco, in which the rudimentary granulated post- 

 frontal crest is slightly developed, the carapace is minutely granulated and 

 the eye peduncles are rather slenderer. 



It will be observed that the specimens differ in some particulars from 

 Milne Edwards' description, particularly as regards the antero-lateral margins 

 of the carapace, which although not denticulated are very distinctly granulated. 



The specimens from Milligalli may very probably be identical with the 

 form designated by S. I. Smith, Pseudothelphusa 'plana, and may be specifically 

 distinct ; the largest female, whicli is nearly the same size as the specimen 

 from Tumbaco, is proportionately slightly narrower, measuring as follows : — 

 $. Length of carapace about 7 lines (15 millims.) ; breadth of carapace 

 nearly 12 lines (24'5 millims.). There are examples of both varieties, from 

 Guatemala, in the Collection of the British (Natural History) Museum. 



2. Aratus Pisoni. 



Scsarma Piso)ii, M. Edwards, Hist. Nat. Crust., ii, p. 76, pi. xvi, figs. 4, 5 

 (1837). 



Amtus Pi-ioiii, M. Edwards, Ann. Sci. Nat. (3me serie), Zool. .\x, p. 187 

 (1853) ; Kingsley, Proc. Acad. Nat. Sci. Philad., p. 218 (1880). 



Hab. Guayaciuil. A single female specimen. Length of carapace about 

 6h lines (1 3'5 millims.) ; breadth of carapace about 6h lines (13-5 millims.). 



The specimen is a small one and somewhat faded; but it cannot, I think, 

 Ije distinguished specifically from .specimens from Jamaica and Brazil in the 

 Collection of the British Museum. The occurrence of this species on the 

 Western Coast (at Nicaragua) has already ))een noted by Kingsley. On the 

 Eastern Coast its range extends southwards to Rio de Janeiro, Brazil (Heller). 



At Guayaquil two Cralis were collected with Aratus Pisoni which probably 

 belong to different species of the genus Gelasimus, but their identification must 

 remain uncertain since one is a female, and the other, although a male, has 

 lost the larger chelipede. In both of these specimens the front between the 

 eyes is broad, and the antero-lateral margins are anteriorly nearly parallel, 

 and convergent from a point placed at some distance behind the exterior angles 

 of the orliits, as in several American species of this genus. 



