158 A. Alcock — Carcinological Fauna of India. [No. 2, 



in the Journal of the Linn^an Society (Zoology), Vol. XIV. 1879; 

 and by the same author's Report on the l Challenger ' Brachyura ; and to 

 these important works I have here to acknowledge my great indebted- 

 ness. 



I have not, however, been able to give my complete adherence to 

 the classification proposed by Mr. Miers, further than to accept the 

 previously adopted division of the Oxyrhyncha into two groups of 

 equal value — the Maioids and the Parthenopoids. To these groups, I 

 would, following Dr. Claus, give the rank of families — Maiidse and 

 Parthcriopidee. 



But to further sub-divide a group like the Maioids — in which we 

 find, as Miers himself remarks, every reasonable gradation of form 

 from Stenorhynchus to Pericera — into separate families, as is done by 

 Miers, involves, I think, an unnecessary and ivnphilosophical interference 

 with the meaning of the term ' family.' 



Nor is anything gained, from the point of view of the practical 

 systematist, by establishing families which overlap in all direc- 

 tions. 



I am so much indebted to the works of Mr. Miers, that I should be 

 loath to criticize them in any but a friendly spirit. But it seems to me 

 that while Mr. Miers has recognized the value of certain characters 

 round the developments and modifications of which the Maioid Crabs 

 easily cleave into most natural groups, he has proceeded in practice to 

 ignore in great measure the value of his own generalization. 



It appears to me that Mr. Miers' families of Maiinea consist each 

 of a quite natural nucleus hidden in a loose artificial wrapping. 



Beginning with the Inacltidoe of Miers, we find a natural group, 

 typified by such forms as Leptopodia and Inachus, linked with forms like 

 Anamathia, Xenocarcinus, Huenia, Pugettia, Acanthonyx, Doclea and 

 Stenononops, none of which are any more nearly related to Leptopodia 

 and Inaclnis than they are to any other Maioid. 



In the Maiidse of Miers again, we find a most arbitrary jumble of 

 forms. Amid the confusion, however, we can discern a large natural 

 nucleus, typified not, it is true, by Main, but by such forms as Egeria, 

 Chioncecetes, Pisa, Naxia, etc. ; but these are no more nearly related to 

 Maia, Paramithrax, Schizophrys, Criocarcinus, and Micippa than they 

 are to any other Maioid. 



The third family, Periceridse, is even more bewildering; but as 

 Miers himself, in his Report on the ' Challenger ' Brachyura, has distri- 

 buted many of his original Periceroid genera among the other two 

 families, it would be unjust to enter into any detailed criticism of this 

 family now. 



