1880.] NATURAL SCIENCES OF PHILADELPHIA. 3T 



margin regularly arcuate. Is very closely allied to T. Isevis, but 



differs in the flatter carapax, the concave front, and the regularly 



arcuate lo^j^er margin of the hands. In all other respects Mr. 



Wood-Mason's description and figures (Journal Asiatic Society of 



Bengal, vol. xl, p. 201, PI. xiv, fig. 1-6) would well appl}' to it. 



Ceylon. 

 Thelphusa rugosa nov, 



Carapax depressed, cervical suture and post frontal crest well 



marked, the crest interrupted. Front nearly straight ; proto- 



gastric region nearl}^ smooth ; epibranchial tooth small, directed 



inward, lateral portions of carapax with transverse ruga? as in 



mau}^ Grapsi, the margin of the anterolateral portion obscurely 



crenulate. Chelipeds subequal ; the outer surface of meros and 



carpus with squamose rugae, the rugae on the hands indistinct. 



Carpal joints of the first three pairs of ambulator}^ feet with the 



sides cristate ; dactjdi pointed. 



Ceylon. 

 Length 26 mm., breadth 32 mm. 



This species is nearest T. denticulata, but will be readily 

 identified from that species by the more crenulated margin 

 between the orbit and the epibranchial tooth, and by the rugae on 

 the lateral portions of the carapax. 



Acanthocyclus gayi Edwards and Lucas. 



The type of this species is in the museum of the Academ3^ 



