12 Memoirs of the Indian Museum. [Vol. VII, 



character running through the Pseudacanthinae. The second American sub-family may be 

 called the Proculinae. It includes forms in which the outer tubercles are rudimentary or 

 absent ; the clypeus is almost always exposed, though never separated from the frons by a 

 distinct suture. The third and last American sub-family, the Passalinae, includes forms 

 in which the outer tubercles are well developed and usually very widely separated, the 

 clypeus being hidden in almost all species. 



The classification of the Indo-Australian Passalidae was recently revised (Gravely, 

 1914c, pp. 191-204, 316-318 and 328-330). They fall into two distinct sections, of which 

 one forms the sub-family Aulacocyclinae. The results of my previous work on the 

 classification of the other section have been summarized as follows (1914c, pp. 336-337): — 

 ' The second section has been sub-divided into the Pleurarius, Aceraius, Macrolinus, 

 Kaupioloides, Protomocoelus, Hyperplesthenus, Gnaphalocnemis, Plesthenus, Gonatas, 

 Tarquinius and Leptaulax groups. Of these groups the first three and the last two 

 appear to be of most importance, and have been provisionally ranked as subfamilies, 

 the remainder being put together into a single subfamily which takes its name from the 

 genus Gnaphalocnemis. Their rank cannot be finally settled without reference to American 

 and African species." 



The number of subfamilies thus recognized is undoubtedly too great in comparison with 

 the classification of American and African forms outlined above, and may advantageously 

 be reduced to two. One of these, the Leptaulacinae, remains as defined in my previous 

 paper. The second, which may be called the Macrolininae, includes all the rest. 



The above enumerated subfamilies of Pa?salidae may now be defined thus : — 



^ The distal ends of the anterior coxae projecting beyond the 



surface of the intercoxal portion of the prosternurn, which is 



entirely hidden except in aberrant Chinese and Japanese 



forms, where it is exceptionally strongly keeled ; the usual 



paired cephalic tubercles absent, the middle lower tooth 

 lV almost always fixed . . . . . . . . Aulacocyclinae, p. 13. 



The distal ends of the anterior coxae about on a level with the 



general surface of the intercoxal portion of the prosternum, 



which is visible between them ; at least one pair of the usual 



paired cephalic tubercles present in most species ; the middle 

 V, lower tooth always jointed on to the mandible . . . . . . . . 2. 



f The anterior lower tooth more or less columnar, at least on the 



right side, being compressed before and behind or even 



concave behind ; or all three terminal teeth directed forwards, 



and arranged in a line one above another ; or the dentition 



incomplete ; the head always symmetrical (American and 



African forms) . . . . . . . . . . . . 3. 



The anterior lower tooth conical, compressed above and below ; 



the lowest terminal tooth directed inwards and set a little 



behind the other two ; the head often asymmetrical — always 

 V so in forms with reduced dentition (Indo-Australian forms ). . .. .. 6. 



J 



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