CERAMBYCiaE 29! 



The femora of the male are always much stouter than those of 

 the female and strongly claviform, and the abdomen protrudes more 

 behind the elytra in the latter, which differs also from the male in its 

 more elongate form of body and relatively smaller prothorax; but 

 I have noticed no decided differences otherwise, either in structure 

 or sculpture, in those cases where the two sexes come from the same 

 source and undoubtedly pertain to the same species. The very 

 remarkable bipartite sculpture of the male femora, described above 

 under solida and femoralis, does not seem to affect any other species 

 of the genus. 



Tribe MONOCHAMINI. 

 Monochamus Serv. 



The elytral apices are notably variable in this genus between 

 rather wide limits, but, with series at hand, several sufficiently 

 obvious groups may be denned as below. In scutellatus, for example, 

 the tips are never dentiform, but they vary from an acutely denned 

 right angle at the suture to an even and rather broad arcuation ; in 

 obtusus all the examples at hand have the sutural angle well rounded, 

 without trace of prominence; in maculosus, oregonensis and some 

 others, there is, normally, an obtuse sutural prolongation, which 

 may however be lost in certain individuals. The antennal joints 

 in large males sometimes seem to be proportionally longer than in 

 small examples, and there is considerable sculptural variability; 

 for example in notatus Drury (confusor Kirby), the elytral punctures 

 are well separated and not notably graniform, but, in one specimen 

 before me from the Adirondacks, these become very strong and so 

 dense as to produce a rugose aspect; much latitude for individual 

 variation, therefore, has to be allowed, but notwithstanding this, 

 the number of true species admitted by Dr. Horn is too small by 

 several. Those which seem entitled to the specific status may be 

 defined as follows: 



Elytra with the sutural angle prolonged in a slender spine; body large, 

 parallel ( 9 ) or with cuneiform hind body (cf ) ; color pale chocolate- 

 brown, mottled with darker brown and white, especially dark near 

 the base, laterally before the middle and in spots thence to the tip, 

 a broken oblique white lateral fascia at basal fourth, another some- 

 times at the middle and a third always visible near apical fourth 

 especially noticeable; punctures toward the humeri becoming moder- 



