128 H. C. FALL. 



Antennae of male never flabellate, at most pectinate; front tibiae not toothed 

 and denticulate externally; form and sculpture not obviously differ- 

 ent in the sexes 3. 



3. Head in repose received upon the under surface of the prothorax 4. 



Head very strongly deflexed and retracted, the mandibles nearly or quite, 



reaching the metasternum 5. 



4. Prothorax not excavated beneath, the head free Dryophilini. 



Prothorax excavated beneath for the reception of the head Anobiini. 



5. Trunk not grooved for the reception of the middle and hind legs; anterior 



coxae contiguous and depressed ; head impressed or excavated beneath 

 for the reception of the antennae; metasternum not lobed in front; 



form oblong or elongate oval Xyletinini. 



Four posterior legs received in appropriate excavations of the metasternum and 

 first ventral segment; metasternum frequently lobed in front; form 

 varying from elongate-oval to globose Dokcatomini. 



6. Prothorax not distinctly excavated beneath, disk in the female acutely aspe- 



rate anteriorly ; form cylindrical Ptilinini. 



With the exception of the introduction of the Hedobiini, reasons 

 for which have already been given, the removal of Petalium, Theca 

 and Eupactus to the Dorcatomini, and some minor changes due 

 largely to the amplification necessitated by the larger material 

 studied, the above division into tribes and the sequence of genera 

 which follows is not very different from that proposed by LeConte. 



Following this scheme of arrangement, the genera form a nearly 

 orderly sequence from those in which the head is but little deflexed 

 and the members slightly contractile, to those in which the strongly 

 deflexed head completely shuts in the pro- and mesosterna, and in 

 which the antennae and legs are received in appropriate excavations. 

 I have used the words "nearly orderly" above because of the genera 

 Petalium, Theca and Eupactus, which it seems quite impossible to 

 place satisfactorily in any linear arrangement. For reasons stated 

 under the Dorcatomini it seems more appropriate to associate them 

 with that tribe than with the Anobiini as was done by LeConte. 



Hedobiini. 

 The principal characteristics of this tribe have already been set 

 forth, and further details will be found in the generic diagnoses 

 which follow. Our genera are only two in number and easily sepa 

 cable by the form of the antennae. 



Antennae filiform, similar in the sexes He<lobia. 



Antennae pectinate in the male, seriate in the female Eucrada. 



