178 BULLETIN 407 



Hickory feeding 'b Locust feeding 'b 



3. Terminal or nth joint of antennae 3. Terminal or nth joint of antennae 

 full ? longer than the penultimate, and scarcely | or \ longer than the penultimate, 

 composed of two portions connected by the division into two portions barely 

 an indistinct connate suture foreshadowing discoverable, and the terminal portion 

 a 1 2th joint, (as in Purpuricenus tf and not suddenly slenderer from base to tip. 

 in Tragidion annulatum^ Lee.,) which 



suture is more distinct on the inferior 

 surface. The basal portion of the nth 

 joint as long as joint 10, the terminal 

 portion, which is suddenly slenderer from 

 base to tip, more than as long as joint 10. 



4. Elytra widened at base and tapered 4. Elytra much less tapered and shaped 

 towards their tip, so that the two together exactly as in the 9 of both the two races, 

 just before the extreme tip equal the basal i.e., with the lateral edges subparallel. 

 width of one of them. 



5. The 2nd or W-shaped band on the 5. The W-shaped band on the elytra 

 elytra in two of the Philadelphia specimens colored yellow, exactly like the other 

 and the Illinois specimen whitish, in the bands, in all my 15 specimens. 



other Philadelphia specimen centrally 



whitish, but decidedly varied with yellow . : > 



on the two exterior arms of the W. 



6. Legs proportionally %-% longer and 6. Legs proportionally no longer or 

 stouter than in 9 . stouter than in 9 . 



The 9 antennae are exactly alike, being in both races a little more than as long 

 as the body, with the terminal joint equal in length to the penultimate or perhaps 

 very slightly longer, and no perceptible difference in the robustness of the whole antenna. 

 The general appearance of the two 9 9 and of the cf of the locust-feeding race is 

 very similar, but, owing to the shape of the elytra, the cf of the hickory-feeding race 

 has a different and Leptura-like habit. So closely indeed does the cf of the locust- 

 feeding race resemble the 9 of both races that until a recent period I had always sup- 

 posed that all my specimens of that race some 30 or 40 in number were 9 9 , and 

 that the unique cf which I possessed of the hickory-feeding race, was the normal cf of 

 the species. In all the 9 9 of both races the W-shaped band on the elytra is as 

 yellow as the other bands. Whether there is any distinction in the larva state is 

 unknown, as the larva of the locust-feeding form has never yet been critically 

 examined. * * 



* * * It is a doubtful and disputed question in Entomological Archaeology, whether 

 Drury's name pictus or Forster's name robiniae has the priority, as Drury was the 

 first to describe the insect, and Forster the first to name it. We may therefore, 

 with even-handed justice, appropriate the name robiniae to the locust-feeding race 

 with short and slender cf antennae and leg, which appears in September, and the 

 name of pictus to the hickory-feeding race with long and robust cf antennae and legs, 

 which appears in May and June. 



Both Forster's and Drury's descriptions, however, show that the species 

 they refer to are identical, and are the ones which inhabit the locust. The 

 names Cyllene robiniae and Cyllene pictus are, therefore, synonymous, 

 and Walsh's application of this name to the hickory species was accordingly 

 unjustified. 



Riley (1876) gave a brief description of the larva and imago of the 

 hickory borer, together with a few notes on its life history, and men- 

 tioned the characteristics distinguishing it from Cyllene robiniae. 



