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251 



An account of the larva and the pupa was read by me at the Ann 

 Arbor meeting' (1885) of the Entomological Club of the A. A. A. S. 

 Thi« was printed in Entomologka Americana, I, p. 174, and the pro- 

 visional name Cossus ahii was proposed. It was not until June, 1888, 

 that I obtained an imago, which proved to be Hepialus argenteomacu- 

 latus. 



The descriptions were as follows : 



, Length, 1.5 to 1.8 inches. Subcyliudrical, taperLug very slightly at extremities; 

 slender. Width of body, 0.25 of an inch. Length of smaller ones, 0.8 inch. The 

 head is light yellowish-brown above, black about the mouth parts, hemispherical, 

 smooth or slightly roughened, with a few dark dots, from which arise dark hairs, 

 usually worn off the vertex of the larger examples. The second ring is smooth ; lighter 

 colored than the head. Above the spiracle, on either side, there are three black spots, 

 situated at the coruersof a right-angled triangle ; the upper one, at the right angle, bears 

 a coarse brown hair; the other two have liner, lighter-colored hairs. The top of the 

 third ring is likewise smooth and brownish. The remaining body surface, except 

 the yellowish piliferous spots and top of ring 13, is white. The longer hairs on the 

 posterior rings are black. The body rings are strongly folded transversely. The yel- 

 lowish dorsal spots bear brownish hairs ; the anterior, larger pair are situated near 

 together on the broadest transverse fold; the smaller, posterior pair are situated on 

 a narrower fold, and much farther from the slight dorsal furrow. The stigmata are 

 broadly elliptical; the rings narrow, black, scarcely raised above the surface; the 

 color within the ring light brown. The legs are yellowish ; hooks black ; the proii- 

 legs with very many booklets. 



The pupa is slender, length 1.6 inches, width of thorax, 0.33 inch, but slightly 

 curved and of unusually uniform diameter, smooth, under a lens transversely striate, 

 the three anterior rings black, shagreened ; on the prothorax there are two conical 

 protuberances which in profile under a strong lens prove to be double pointed ; on 

 the clypeus are two gouge-shaped spines, shining black on outer half, and on the 

 upper roughened base of each of these there is a small conical tooth ; on the under 

 side of the head case, below the gouge-like spines, is a pointed spine directed for- 

 ward; back of this are two smaller cusps, one either side of ventral line, and still 

 farther back, apparently over the first tarsal joint of the fore legs, are two smaller 

 points. The transverse rows of dorso-abdominal teeth are as usual, but the teeth are 

 exceedingly fine, increasing in size but little posteriorly ; the black, blunt, anal seg- 

 meut bears several small black conical teeth on either side. 



I have found no parasite of this larva, but I have seen that the 

 woodpeckers are its deadly foes. In April, 188G, I had a favorable op- 

 portunity to search for the borer and was astonished at the scores re- 

 moved by these birds. They often drill through a deep layer of wood ; 

 often two holes are made one above the other, the purpose being ob- 

 vious. The morsel is evidently located, or its burrow rather, by sound- 

 ing, as I noticed many instances in which a row of punctures sur- 

 rounded the base of the alder. The destroyers are sometimes mistaken, 

 for I found their drillings, evidently made in search of this larva, in 

 sound wood in which there were no borers, but these were few com- 

 pared with the successful trials. 



Is it the activity of these birds that prevents the abundance in the 

 forest of certain borers, e. g., Aegeria acerni, whilst the same insect is 

 often destructively abundant in the ornamental maples of cities and 

 villages ? 



