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worn off the vertex of the larger examples. The second ring is smooth, lighter color- 

 ed than the head; above the spiracle on either side there are three black spots situ- 

 ated at the corners of a right-angled triangle, the upper one at the right angle, bears 

 a coarse brown hair, the other two liave finer, lighter colored hairs; the top of the 

 third ring is likewise smooth and brownish; the remaining body surface except the 

 yellowish pihferous spots and top of ring thirteen is white; the longer hairs on the 

 posterior rings are black. The body rings are strongly folded transversely; the 

 yellowish dorsal spots bear brownish hairs; the anterior larger pair are situated rather 

 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 prop legs 

 with very many hooklets. 



The pupa is slender, length 1.6 inches, width of thorax .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 underside of 

 the head case, below the gouge-like spines is a pointed spine directed forwards; 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 segment bears 

 several small black conical teeth on either side. 



I have mentioned this insect above as an undetermined Cossus; that 

 it is one of the Cossidze, there can be, I think, no doubt and as I un- 

 derstand the descriptions of the preparatory stages of the genus Cossus, 

 it seems to me that it belongs to that genus, therefore I will for brevity 

 of referrence call it provisionally Cossus Alni. It certainly is clearly 

 distinct from C. Centerensis whose larva and pupa I have had an oppor- 

 tunity to examine from poplars at Corunna, Mich. ; in fact it appears to 

 be distinct from any species, whose history is know. It may prove to 

 be one of the doubtful or partially known species. I am aware that Mr. 

 Lintner has referred to a Cossus which bores in the trunk of white birch; 

 I am also mindful that insects are as a rule pretty good botanists and 

 that B etui a and Alnus are closely related plants, so this insect may prove 

 to be the one discovered in the birch by Mr. Lintner. It ought not to 

 be a difficult matter to obtain the moth in May or June next. 



For the above entomological guessing, my first attempt, I trust 

 you, my friends, will pardon me; as most of you have at sometime and 

 in some degree, committed the same error, I think you will. 



Prof. Lintner says that the larva referred to as having been found by 

 him in birch seems also a root borer; all those found being near the ground. 

 He found only one broken pupa which is still in his possession and he 



