175 



that Dr. Hagen and I are looking on opposite sides of the shield, I 

 see in all species of the same genus, in the present case, in all Colias, 

 derivation from a single ancient species. In course of ages, under 

 altering conditions, in many climates, different colonies have settled 

 here and there throughout the broad continent; have acquired certain 

 decided peculiarities; the intermediate links between these colonies 

 have been lost, mostly by absorption into the strong forms; these are 

 plainly now breeding true to their own types, and have all the charac- 

 teristics of separate species. 



In Dr. Hagen's view, these colonies can never separate; all the forms 

 sprung from one original type, form, or species, must be " united 

 with it," and altogether are neither more nor less than one species, just 

 as the varieties of Philodice are all still Fhilodice. So all the many 

 species, which, as he says, "are characterized by differences falling in 

 the wide range " of what any given species may present " must be 

 united with it." Even in the American Coliades, under the statement 

 of his own views, the Doctor really ends by making nine distinct spe- 

 cies, much to my astonishment. That is to say, nine centres of crea- 

 tion in N. America alone! 



After having stated the radical difference which exists between the 

 views held by Dr. Hagen and post-diluvian naturalists generally, in 

 which category I include myself, it is hardly necessary to follow 

 this Colias paper further. The same error runs through every page of 

 it. But I will endeavor, as brielly as I may, to notice the Doctor's com- 

 ments on certain species. The paper leads off with C. Edwardsii, a 

 species described and figured by me in 1870, after the MSS. name 

 given it by Dr. Rehr, one of the acutest lepidopterists we have had in 

 this country, in honor of Mr. Henry Edwards. It is used here as a 

 sort of decoy for tolling nearly all other species, and passing them 

 over to C. Interior. At the end of the farce it is Interior which gets 

 off with the swag. At first the whole 129 examples are Edwardsii, in 

 the interval between the acts they are this and that, but at the end 

 every fellow of them is Interior. These 1 29 examples appear to com- 

 prise every Colias taken on this memorable foray (see page 152), and 

 my positive friend assumes that the 83 3 and 46 $ are Edwardsii. 

 That is a remarkable catch. Edwardsii has hitherto been one of the 

 rarest of Colias, but that in any spot in W. T. it should be taken by 

 the hundreds, in a colony apart from any other species, is wonderful ! 



Some of these Edwardsii, however, our author says, he cannot dis- 

 tinguish from Alexandra, some from this species some from that. Al- 

 gjcandra was described in 1863 and figured in 1868. Both these spe- 

 cies stand in same volume of B. N. A., and if, as the doctor says, 

 " Alexandra and Ediuardsii belong to one and the same species," I 

 do not see how he knew which was one and which the other, out of 

 his 129 examples, and why Alexandra, as the eldest, did not capture 

 the other. The two species at all events are closely related, :ind I 

 should not be at all surprised if breeding hereafter shows that they are 

 forms of one species, perhaps seasonal. So far, however, we have no 

 knowledge except what may be got from the dried insects. The un- 

 der side of Alexandra is of a delicate gray-green, and the discal spot 



