356 FIFTH KEPORT OF THE ENTOMOLOGICAL COMMISSION. 



bands that the beetle is nearly all of the shade of deep golden yellow 

 peculiar to the flowers of the golden rod, and thus the insect is an 

 interesting case of " protective mimicry," being protected from the 

 attacks of birds, etc., by their liability to be confounded with the 3^el- 

 low heads of the golden rod. 



The best account of these insects has been given, as follows, by 

 Harris : 



In the mouth of September these beetles gather ou the locust trees, where they may- 

 be seen glittering iuthe sunbeams with their gorgeous livery of black velvet and gold, 

 coursing up and down the trunks in pursuit of their mates, or to drive away their 

 rivals, and stopping every now and then to salute those they meet with a rapid bow- 

 ing of the shoulders, accompanied by a creaking sound, indicative of recognition or 

 defiance. Having paired, the female, attended by her partner, creeps over the bark, 

 searching the crevices with her antenme, and dropping therein her snow-white eggs, 

 in clusters of seven or eight together, and at intervals of five or sis minutes, till her 

 whole stock is safely stored. The eggs are soon hatched, and the grubs immediately 

 burrow into the bark, devouring the soft iuner su))8tance that suffices for their nourish- 

 ment till the approach of winter, during which they remain at rest in a torpid state. 

 In the spring they bore through the sap-wood more or less deeply into the trunk, the 

 general course of their winding and irregular passages being in an upward direction 

 from the place of their entrance. For a time they cast their chips out of their holes 

 as fast as they are made, but after a while the passage becomes clogged and the bur- 

 row more or less filled with the coarse and fibrous fragments of wood, to get rid of 

 which the grubs are often obliged to opeu new holes through the bark. The seat of 

 their operations is known by the oozing of the sap and the dropping of the sawdust 

 from the holes. The bark around the part attacked begins to swell, and in a few 

 years the trunk and liuibs will become disfigured and weakened by large porous 

 tumors, caused by the efforts of the trees to repair the injuries they have suffered. 

 According to the observations of General H. A. S. Dearborn, who has given an ex- 

 cellent account of this insect, the grubs attain their full size by the 20th of July, 

 soon become pupa), and are changed to beetles and leave the trees early in Septem- 

 ber. Thus the existence of this species is limited to one year. 



Dr. Horn, who has observed C. pictus in the hickory, states (Proc. Ent. Soc. 

 Phil., i, 30) that its excavations are immediately subcortical. "Unlike the Clytus 

 eryihrocephalus, which also bores in the hickory, its course is not in a line, but it 

 bores in every direction, making extensive excavations. Its borings are coarse and 

 sawdust-like, and are packed with considerable firmness. When about to become 

 pupa the larva bores for a sliglit depth into the wood, and for a distance of about 3 

 inches. The aperture is closed with some very coarse splinter-like borings, and after 

 having turned its head iuthe direction of its previous subcortical dwelling, it under- 

 goes its transformation, and requires about two and sometimes three weeks for 

 becoming a perfect insect." 



As is well known, Cyllene pictus attacks the walnut and hickory, 

 and occasionally the honey locust, but those individuals living in these 

 trees, unlike the locust brood, evolve the beetle in June, according to 

 Walsh, who has claimed that the males of the hickory brood differ 

 from those of the locust brood in having " much longer and stouter 

 legs and much longer and stouter antennae, and in having [their bodies] 

 tapering behind to a blunt point"; on the other hand the females are 

 not distinguishable, nor the larvte. On this account Mr. Walsh re- 

 garded the locust and hickory broods as representing two distinct 



