CARDISOMA OBESUM. 35 



55 mm., length 47 mm. Length of the hand of the lar- 

 ger leg 45 mm. 



Breadth of carapace (Q) 60 mm., length 48 mm. 



19. Cai'disoma obesiim, Dana, 



Milne Edwards, 1. c. pag. 205. 



There are two specimens of Cardisoma in the collec- 

 tion, collected at the island of Sumatra, which I think I 

 may refer to the species described by Mr. Milne Edwards. 

 These specimens agree in the most essential characteristics 

 with Cardisoma hirtipes Dana, as regards for example, the 

 relative situation of the almost invisible epibranchial tooth, the 

 form and size of the orbits and the very much hairy pterygosto- 

 mian regions ; but the carapace is comparatively much more 

 enlarged , the branchial regions are very tumid and there is 

 no distinct raised lateral line defining the lateral margin. 



The very convex lateral surfaces of the carapace are 

 smooth. Anterior legs nearly equal , hands as long as 

 the breadth of the carapace , arm and wrist entirely smooth. 

 In one specimen from Padang the fingers are widely sepa- 

 rated , in the other, collected in the northern part of Sumatra , 

 scarcely at all; I think these variations to be individual. 



The first joint of the external antennae is somewhat 

 more enlarged than that of Card, hirtipes , but not in 

 such a degree as in Card, carnifex. Breadth of carapace 

 (cT) (the tumid lateral parts of the carapace included) 

 83 mm., length 65 mm. Length of the hand 85 mm. 



This form bears evidently the same relation to Card, 

 hirtipes as Card, urvillei does to Card, carnifex. 



There is one more beautiful male specimen of Car- 

 disoma in the collection, that agrees almost entirely with 

 Card, obesum, but the branchial regions are still more 

 tumid , in such a degree , that the middle part of the 

 carapace is concave. 



I cannot decide whether this form belongs to a proper 

 species or not, though I think it to be prol)able; the an- 



Notes trom. tlie Lcydeii Museum, "Vol. II. 



