210 H. C. FALL. 



Catorama and Protheca, placed by LeConte in the Xyletinini. 

 Granting that Petalium, Theca and Eupactus should be included in 

 the Dorcatornini, what then is their relation to each other and to 

 the other genera of that group. The three genera in question pos- 

 sess in common a peculiar character which was noted by LeConte 

 in Theca and Eupactus, but was evidently overlooked in Petalium, 

 in which, indeed, it is more feebly developed. This consists of the 

 expansion of the apices of the anterior coxse into flat transverse 

 horizontal plates which are coarsely sculptured and form a portion 

 of the exposed lower surface of the insect when contracted. The 

 articulation of the trochanter with the coxa is posterior rather than 

 apical, and the mandibles lie in contact with the coxal plates in 

 repose This extraordinary structure seems of sufficient import- 

 ance to warrant the close association of these genera, but it must be 

 admitted that there is little else that indicates either mutual rela- 

 tionship or any close affinity to the other genera of the tribe. The 

 singular structure of the antennal club and the double ventral 

 sutures in Eupactus, the mesosternal structure in Theca and the 

 enormously developed metasternal lobe in Petalium are all charac- 

 ters so unique in kind or in degree' of development as to show a 

 somewhat unusual individuality within tribal limits. I have placed 

 these three genera at the head of the Dorcatornini, though recogni- 

 zing that they constitute an obvious interruption to an orderly 

 sequence of genera, Lasioderma and Megorama of the Xyletinini 

 forming a natural transition to Catorama and Cryptorama of the 

 Dorcatornini. They seem equally out of place, however, in any 

 other position, and since we cannot avoid the necessity of a linear 

 arrangement it has seemed best to give them their present position 

 because of a certain affinity to the Anobiini discernible in the elon- 

 gate form, feebly elevated disk of the prothorax, internally widened 

 posterior coxal plates and the less deeply excavated first ventral 

 segment of Petalium. 



Our fauna is far richer than the European in this tribe, which is 

 there represented by seven genera and thirty species as compared 

 with our eleven genera and upward of one hundred species. Of 

 the European genera, four — Mesothes, Mesoccelopus, Anitys and 

 Eutheca — do not appear with us. Both Mesothes and Mesocuclojins 

 differ from all our genera in the uniformly serrate antennae without- 

 enlarged outer joints; the former is elongate, the elytra with a sin- 



