On Pronuba Yuccasella. 143 



spots of the Colorado specimens, except No. 3, while none of the Col- 

 orado specimens have an}' of the spots of opunctellu, except No. 3, even 

 when the spots number as many as thirteen.* So the eight specimens 

 scarcely varied as to size, while the Colorado specimens range from 

 less than six lines in expanse of wings, to ten or more. The species 

 thus resemble each other, and other Hyx)onomeutidcv, in being white 

 with black spots, which are sometimes absent from the wings of the 

 Colorado specimens; the}' differ in the number and position of the 

 spots, in the fact that //. 5punctella is constant in this respect, while 

 the Colorado specimens are exceedingly variable, not only as to the 

 spots, but as to the size. No inference that the insects belong to the same 

 species can be drawn from the fact that spot No. 3, at the end of the 

 disc, is common to both; because it is common, not only to them, and 

 numerous other species of Tineina, but also to many species of widel}- 

 separated families of Heterocera; and this remark likewise applies to 

 the row of spots around the apex (6 to 13, fig. 1), which, however, are 

 absent iu all the specimens o^ 52Junctella. It is, therefore, evident to 

 me, that Prof. Rile}- is iu error in referring the five Colorado specimens 

 to SpuncteUa. Is he equally wrong in denj'ing that they belong to 

 P. yuccasella^ This question, however, can not be answered by argu- 

 ment, or by assertion, but only b}' examinations of specimens made; it 

 may be by those "other "observers," invoked \>j Prof. Zeller, for the 

 study of Pronuba. I hope to have the opportunity to satisfy myself at 

 least about it in Colorado next Summer, but until then must defer 

 an}^ attempt at a solution of the diflScult}-. Situated as I was, in Col- 

 orado, I could not, and did not, attempt to preserve an}^ large collec- 

 tion of any one species, though in the case of this, the most abundant 

 species that I found there, many were observed; of the comparatively 

 few that I kept, man}^ were destroyed before I reached home. 



I have seen traces oi Pronuba larvae in seed pods of yuccas at var- 

 ious places in Colorado, but the only place where I collected the imago 

 was on theplains^ about nine miles north of Colorado Springs, and thence 

 to five miles east of the mountains. It was there that I took the speci- 

 mens referred by Mr. Riky to opunctella. Both the spotted and un- 

 spotted forms were found there, in great abundance, always in company 

 with each other — always in the flowery of the yuccas, never elsewhere — 

 never engaged in feediny, always quietly reposing on the inside of the 

 perianth. I observed them as the}^ sat in the flowers, and saw no 

 difference in their appearance, or in their position in repose, nor in 

 their mode of flight when disturbed. I took man}- specimens in collect- 

 ing bottles, killed them, and examined the neuration of the wings of 



* The sketch then made is now before me. It is unquestionably the wing oi P. i/uccasella; 

 but unfortunately my notes do not show whether or not it was one of the spotted specimens. 



