280 A. Alcock — Gar etiological Fauna of India. [No. 3, 



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

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

 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 Grapsidse has much to recommend it. 



I gladly follow Milne Edwards in recognizing the Hyrnenosoma 

 group as a tribn principale not 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 Bhizopinse (Stimpson, Miers), 

 the Hexapodinse, the Palicidse (which include Gymopolia formerly 

 classed with the Dorippidae), and the new family Ptenoplacidse. 



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

 Hyrnenosoma- group from the Pinnoteridse ; in enlarging the Scopimerinse 

 (=Dotinse) at the expense of the Ocypodidse ; in splitting the Grapsinse 

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

 and in removing Gecarcinucus from the Geocarcinidse. 



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

 too often, disregard 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 JDotilla and Scopimera, with Mictyris, with Hyrnenosoma 

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

 with the Bhizopinas. 



Again by the exclusion of Scopimera and Dotilla and by the 

 inclusion of the Gonoplacidm, Miers family of Ocypodidse becomes 

 unnatural and incomplete. 



I follow Miers in treating the Bhizopinse as a subfamily of Garcino- 

 placidse. 



Ortmann obviates some difficulties by separating Gonoplax and 

 Ommatocarcinus from the Garcinoplacidse as a distinct family, and by 

 altogether removing the Hymenosomidse from the Oatometopes. 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 



