280 Carcinological Fauna of India. 



In grouping the genera of the Orapsidse I have departed very little 

 from the arrangement of Milne Edwards, who recognized — though hia 

 successors have ignored it — the independence of the Varuna group. 



I have adopted Dana's family of Geocarcinidse, but with some 

 hesitation, for Milne Edwards* estimation of the group as a subfamily 

 of Orapsidee has much to recommend it. 



I gladly follow Milne Edwards in recognizing the Hymenosovia 

 group as a tribu principale nob distantly related to the Ocypodes and 

 quite distinct from and independent of the Pinnoteres group. 



As regards additions to the Gatometopa as known to and recognized 

 by Milne Edwards, I may mention the Rhizopinse (Stimpson, Miers), 

 the Hexapoditise, the Palicidse (which include Cymopalia formerly 

 classed with the Dorippidas), and the new family Ptenoplacidx. 



From the system of Dana I would dissent only in separating the 

 Symenosoma-gvovL^ from the Pinnoteridss ; in enlarging the Scopivierinss 

 {=Botin$3) at the expense of the Ocypodidse ; in splitting the Grapsivas 

 into two equal groups, — one round Grapsus, the other round Varxma ; 

 and in rem.oving Gecarcinucus from the Geocarcinidse. 



The scheme of classification proposed by Miers seems to me to, 

 too often, disregai'd natural relations without facilitating the recognition 

 of species by way of compensation. 



The most conspicuous instance is the family Pinnoteridse, in which 

 we find Pinnoteres and its kindred included with such undoubted 

 Ocypodoids as Dotilla and Scopimera, with Micfyris, with Hymenosoma 

 and its allies, and finally with Heonapus whose affinities are quite clearly 

 with the Rhizopinas. 



Again by the exclusion of Scopimera and Dutilla and by the 

 inclusion of the Gonoplacidse, Miers family of Ocypodidie becomes 

 unnatural and incomplete. 



I follow Miers in treating the Tlhizopinas as a subfamily of Oarcino- 

 placidas. 



Ortmann obviates some difficulties by separating Gonoplax and 

 Ommatocarcinus from the Carcinoplacidse as a distinct family, and by 

 altogether removing the Hymenosomidee from the Catometopes. By the 

 latter step his Pinnoteridm gain in natural value, as they further do 

 by the restoration of Scopimera and Dotilla to their place among the 



622 



