no. i. BOMBYCINE MOTHS OF NORTH AMERICA— PACKARD. 223 



appreciative in his observations of nature, and thoroughly reliable in his statements. When he looked at the cocoons, 

 he meditatively remarked: "I think I have seen somethimg like that about our place. Indeed, I feel certain I have 

 seen it. but I shall keep a lookout." On the 14th of April, 1894, I received from Mr. Elliot two P. Columbia cocoons. 

 They were attached to a branch of larch, on opposite sides of the same branch, and one about half its length in advance 

 of the other. The son of a neighbor of Mr. Elliot found one on a tree growing at his house and showed it to Mr. Elliot, 

 who saw it was what he was on the lookout for, so they searched the trees and found more. 



The roughened exterior of the cocoons, their dark brown color, with white markings, give them such a close resem- 

 blance to the bark of the branch, that, but for their prominence, they would be extremely difficult to detect, thus forcing 

 on the observer the conviction that larch must be their natural food-plant. On the 3d of May a male moth emerged 

 from one of the cocoons, and on the 6th a female from the other. On the 5th of May Mr. Elliott gave me another cocoon, 

 which gave forth its imago on the 13th, also a female. The male is 3J inches in expanse of wings; the females are 4 and 

 i\. Those from Miss Morton's cocoons are of corresponding dimensions. 



Much doubt was entertained when this moth was first d iscovered as to whether it was a ' ' species " or a cross between 

 two. This question was conclusively settled when Prof. Fernald published his description of its early stages (Can. 

 Ent., Vol. X, p. 43). Miss Morton has succeeded in pairing it with cecropia, and she says the progeny "were all barren 

 and quite different from either parent." When the professor wrote his description he was not confident that it was 

 distinct from gloveri. Since then MissMorton has reared Columbia and gloveri side by side, and she says: "The difference 

 between their larvse is marked in all their stages, whilst the cocoons also differ in size and texture." But she considers 

 columbiato be closer to gloveri than to any other of the genus, and she has had large experience in rearing all of them. 

 It is known by those who have handled them to be an easy thing to separate Columbia cocoons from all the other Platy- 

 samias, but there seems to be some difference of opinion as to what especially distinguishes the moth from cecropia. 

 That Columbia varies somewhat with the locality where found seems certain. The Quebec and Maine forms, as Illus- 

 trated by Bowles and Strecker, do not strikingly resemble the Michigan specimens, which, Miss Morton says, are quite 

 constant in general appearance. Prof. J. B. Smith states that all the columbias that he has seen are very much alike. I 

 sent a specimen from Miss Morton's cocoons to Dr. Brodie, of Toronto, who has given Columbia a good deal of attention, 

 and he said it did not much resemble any Columbia he had; and if he had received it without data, he would have 

 pronounced it a dimunitive cecropia. This to me was decidedly confusing, and set me wondering if there were no 

 points of difference whereby to separate the two species unmistakably. 



When taking a general survey of the two moths, the attention is at once arrested by the smaller size and darker 

 color of Columbia. But there are gradations in these. A very small cecropia is at times obtained. The male from Mr. 

 Elliot's cocoons is extremely dark, whilst a female received from Miss Morton does not perceptibly differ in general 

 shading from some cecropias. So, single specimens could give no certain indication from these differences. 



With six authentic columbias before me, and several fresh examples of cecropia, I will take up that part of Prof. 

 S. I. Smith's original description, where he contrasts the two species, and comment upon it in sections. 



" This species differs materially from S. cecropia. The male has the antenna?, palpi, thorax, and legs much darker. " 

 Correct, as a rule. "The short gray (or whitish) band on the hind part of the thorax is not found in S. cecropia." I 

 have a male cecropia with an indication of it, and in one of the columbias it is not visible. "The discal spots of all the 

 wings are white, instead of dull red with a white center." In one of the columbias the spots are quite red. "The 

 transverse bands of both pairs of wings are white, instead of dull red bordered internally with white." Here, I think, 

 we get the most distinguishing point of difference between the two moths. There is no symptom of red in the bands 

 of Columbia. The "narrow white transverse band," which in some of the specimens would be better termed a line 

 than a band, shades externally into the dark gray of the border, whilst internally it is edged with solid black, which 

 merges into the dark brown of the middle area. This appears to me to be the most conspicuous and constant difference 

 between the two species, and would of itself make it quite easy to separate the moths, regardless of size or depth of 

 coloring. "It wants the broad white band so conspicuous on the anterior border of the secondaries of S. cecropia, and also 

 the reddish tints and markings near the apices of the primaries." The band is not so clear a white, or so broad, but is 

 edged with black, which is absent in cecropia; the tints on the apices are a distinction of degree, and but a slight one 

 at that. 



"The female differs from that of S. cecropia in having the palpi, legs, and abdominal rings dark brown, or almost 

 black, instead of dull red." One of the columbias is not distinguishable from cecropia in that respect. "The discal 

 spots of the primaries are linear, obscure, and parallel to the transverse band , instead of broad, conspicuous, and parallel 

 to the costal border." The spots are more linear, but with a decided tendency toward lunate, thereby being about as 

 much in line with the costal border as with the transverse band. And so far from being obscure, from the absence of 

 red in them, they are more conspicuous than in cecropia. There is a male cecropia before me that would answer that 

 description better than any of the columbias. "The discal spots of the secondaries are small and almost round, instead 

 of large and somewhat triangular." No difference except in size, and the absence of red in the spots of Columbia. 

 "As in the male, it has the white on the hind part of the thorax, and wants the white on the anterior border of the 

 secondaries, and also the red on the apices of the primaries, on the discal spots, and on the transverse bands." What 

 I have said on these parts of the male answers also for those of the female. 



So, then, the only points that are left to me whereby to unmistakably separate Columbia from cecropia are the narrow 

 dull white transverse band edged internally with black and the total absence of a red band.] 



[Mr. Pergande notes that in 1891 Mr. J. W. Allis sent cocoons of S. Columbia from Adrian, 

 Mich., with the statement that some years almost all of the pupae are killed by woodpeckers.] 



