June, 1902.] KeARFOTT : On NoRTH AMERICAN ChOREUTES. 107 



exactly with any I had from this country. I then borrowed from Dr. 

 Dietz all of his specimens and again visited the National Museum and 

 examined carefully all the specimens there (both North American and 

 European). In the meantime Lord Walsingham kindly sent me a 

 pair of silphiella, which he collected thirty years ago in California and 

 Mr. Meyrick a specimen from New Zealand. Miss Murtfeldt also 

 loaned me one of her Missouri bred specimens. Altogether I have 

 had the opportunity for critical comparison of between 250 and 300 

 specimens. 



Almost from the beginning I was convinced that we had a larger 

 number of valid species than was indicated by the late synopses and 

 this conviction was strengthened by the examination of each fresh lot 

 of material, and what was most convincing was that the specimens 

 could readily and easily be separated out into the specific groups I had 

 arranged for them and moreover the species did not intergrade and I 

 have seen no specimens that could doubtfully be referred to two or 

 more species. 



The only stumbling block was the separation oi pretiosana from the 

 nearest allied American form, as it certainly was but little less than 

 sacrilege to attempt to root up and cast away so venerable a trespasser 

 from our lists ; in point of fact I have not a particle of doubt that 

 in the, possibly not very remote, past pretiosana was common to 

 North America, Eurasia, Australasia and possibly South America (I 

 have an unidentified species allied to it from Brazil) but time and en- 

 vironment produce changes and I believe when a change becomes a 

 fixture and invariable new species are evolved. In fact our science 

 is based on evolution ; we generally agree with Darwin that man's 

 ancestor was monkey and while we can also agree that both have 

 many characteristics in common it would be difficult to find one with 

 the temerity to claim they were the same species or even that one is a 

 variety of the other ; and so, I have taken the stand that our Ameri- 

 can forms have all so far departed from the stem forms that we have 

 separate and distinct species. 



I have recognized twelve species and one variety and it is a nice 

 question for the splitters and lumpers to decide whether there are ten 

 varieties of pretiosana or whether they are all pretiosana or whether 

 they are all good species. My conclusions point to the last, for the 

 simple reason there is no trouble to separate out the species. For- 

 tunately, in only one instance, was there a single specimen to repre- 



