63 



valuable, as bringing into a small compass much relating to P. 

 )nachaon and allies that has hitherto been widely scattered, it 

 helps to prove what we evolutionists have long believed, that P. 

 7nachao)i, Hippocrates and allies are all descended from a common 

 stock; but it does not and cannot prove that P. machaon, under 

 any condition of temperature, would ever produce P. hifpoa-ates 

 or P. rutulus. 



]\Ir. Pryer, of Japan, for whom 1 entertain the greatest re- 

 spect as an essentially yzr/c/ naturalist, certainly makes a statement 

 about the size of March specimens of P. hippocrates, which is so 

 astounding that I can only regard it as a slip of the pen ; 2^ 

 inches in expanse would be very small indeed for European P. 

 machaon, most examples of which exceed three inches. I have 

 examined a great number of specimens of P. hippocrates, taken 

 by collectors who have lived in Japan for years, and the difference 

 of size has only varied from 4'/^ inches in the males to five inches 

 in the largest females. I do not mean to say that you could not 

 starve them into smaller insects, but, as a lepidopterist, who has 

 seen probably more Japanese Lepidoptera than any man not liv- 

 ing in Japan, I must be excused if I believe that Mr. Pryer has 

 forgotten to double his measurement or has, at least, vvTitten a 2 

 for a 3 in the note upon this species. 



If, however, we were unquestioningly to accept the statement 

 that some examples of P. hippocrates were smaller than the 

 European species, it would not alter the fact that the former, with 

 its more-produced primaries, the broader dark belt of secondaries, 

 the inner edge of which is scarcely undulated (unlike the Europ- 

 ean insect) and its usually melanistic female is confined to Japan, 

 and P. viacJiaon to Europe, and has no more claim to be called 

 the same species than the Gonepteryx aspasia of Munetries, with 

 its acute falcate primaries, has to be regarded as identical with 

 the broad-winged G. nipalensis\d. specimen of which we have from 

 Nikko, which Pryer confounds with it.* 



Does Dr. Hagen expect us to associate as conspecific all 

 forms descended from a common ancestor? If so, all naturally 

 constituted genera may be called species, and all species repre- 

 sentative forms ; but ciii bono? the species will exist, by whatever 

 terms we know them. I will not say " a rose by any other name, 

 etc," because Dr. Walsh argued forcibly against the truth of that 

 statement, but I will say this, that nothing will be gained by the 

 change. 



Now, as touching the species of Terias, associated by Pryer, 

 and for which, as he considers that too many names have already 

 been proposed, he suggests another, with a view to cure the evil 

 on the homoeopathic plan. It may, perhaps, surprise Dr. Hagen to 



* I did, in:!eed, once receive a specimen of typical G. rkamui from Yokohama, I believe Mr. 

 Pryer sent it in a collection which I received from Mr. Fenton ; I recognized it at a glance as British 

 and this was admitted by Fenton and (if I mistake not) by Pryer also. 



