169 



conclusions, for h\briclizing between butterflies is not an unknown thing. 

 But later it occurred to me to ask Mr. Stretch for the inside history of 

 this expedition, and what part his chief had in collecting butterflies, 

 and what he saw in the field, and what he himself knew of these facts 

 about copulating of specified males and females. He replied, June 9, 

 i<S84, " I went to Washington Territory with Dr. Hagen. By mutual 

 understanding with Mr. Henshaw, I devoted myself to the Lepidoptera 

 and he to the Coleoptera, the result being that I collected fully 95 per 

 cent, of the Diurnals. I do not believe that Dr. Hagen personally 

 collected five liutterflies on the trip, and I am absolutely certain knows 

 nothing about them except seeing the dried specimens ( italicised in the 

 letter), for he never saw them while they were being collected, or labeled 

 at night-time, and I had them in my possession until they were de- 

 livered to him en masse. He was too worn out with the mere effort of 

 moving from place to place to do anything but sleep when he got to 

 camp. . . . Nor does it follo70 that because tico insects were in one 

 paper they were in copulation zvhen taken. They were sometimes play- 

 ing together. ' ' 



This is quite another matter ! It is manifest that the author of the 

 paper spoken of knew nothing whatever of these butterflies, alive or 

 dead, until he opened the envelopes containing them, some months after 

 the expedition separated. He did not see the insects in the field, he 

 did not see them after they were taken, and he merely received from 

 Mr. Stretch certain packages of dried butterflies. He knew, there- 

 fore, just as much about them, and no more, as I knew when I received 

 Christina and Occidentalis from Slave Lake twenty odd years ago. 

 But although the describing of these species of Colias was among the 

 earliest work I did in that way, I correctly mated the sexes, as later 

 observations of collectors show, wolonly and ;;2^r<?/j/ because they came 

 in the same lot, as Dr. Hagen reiterates, but because of the correspon- 

 dence in characters and markings in the two sexes of species. And 

 all lepidopterists determine the sexes of species of butterflies thus, 

 when the dried specimens alone are at hand. There is no other con- 

 ceivable way to do so. But Dr. Hagen did not even suspect that there 

 was some mistake in the matching of his pairs, though in five out of 

 the six cases he says the markings were strikingly different. The last 

 sentence quoted from Mr. Stretch shows how the Doctor came to as- 

 sume that certain males and females had been taken in copulation; he 

 found the opposite sexes in six of the papers. That was all. If he 

 had had any acquaintance with butterflies he would have suspected 

 there must be an error at first glance. 



The outcome of all this is that the facts are baseless and the deduc- 

 tions are in the air. 



While investigating in one direction, I thought it well to try another. 

 On ]). 158, Proc. Bost. Soc. N. H. under C. Astrcea. we are told: " I 



