T. BTSTORTATA (CREPUSCULARTA) AND T. CREPUSCULARIA (bIUNDULARIa). 288 



critical faculty is evident in a note by Mr. T. B. Jefferys, of Clevedon 

 {Entom., xxi., p. 237), where it is assmned, on the most slender data, 

 that " the early and late forms are one and the same brood," although, 

 strangely enough, he makes a reference to the seasonal dimorphism 

 of the undoubtedly double-brooded Selenia hilunaria, a species, the 

 seasonal dimorphism and times of appearance of which run remark- 

 ably parallel with those of T. crepuHcularia. Another similar critical 

 failure occurs when Mr. J, Harrison (Entom., xix., p. 160) states that 

 he fails to separate the specimens of the second brood of T. crepnucu- 

 laria, taken in the New Forest in July, from the specimens of biundu- 

 laria, taken at Barnsley, in May. He states that " he fails to see any 

 perceptible difference." One would certainly not suggest that Mr. 

 C. G. Barrett is Avantingin critical ability ; but all lepidopterists know 

 that the keenest men will sometimes go astray in forming a hasty 

 conclusion from insufficient material, especially when one has already 

 preconceived ideas about the subject in hand. This is the only expla- 

 nation that I can ofter to account for Mr. Barrett's marvellous state- 

 ment [K. M. J/., xxxii., p. 229) : — " The second brood of the brown 

 rrrpKscularia is obviously biiindularia. " 



Yet another factor comes into play. The superficial similarity in 

 ground-colour of the second brood of T. crepuscularia, to that of the 

 only brood of T. hiundularla, has led many lepidopterists, who are 

 quite convinced that we have here two species, into the error of 

 supposing that the second brood of T. crepuscularia is, in reality, a 

 second brood of T. hiundularia. I gathered recently, in conversation, 

 that this was the opniion of that excellent lepidopterist, Mr. C. A. 

 Briggs. Doubleday warned entomologists on this point. He Avrote, 

 in a letter [KntoiD., xix., p. 161), dated Sept. 12th, 1861: — " Crcpm- 



lularia has a second brood Some specimens of the summer 



brood of crcjiHsodan'a very closely approach the spring ones of 

 hiundularia." 



I am not quite sure, but I believe, that Mr, G. T. Porritt was the 

 first entomologist to breed and describe the larvte of these species. 

 At any rate, I find in 187B (Entom., vol. vi., pp. 385 — 386) a descrip- 

 tion of the larva of Tepknma hiundularia. The species was taken by 

 Mr. J. R. Wellman, and the eggs Avere laid in May, 1872. There is 

 no doubt that the species was true biundnlaria. There is no need to 

 quote the technical description, but Mr. Porritt observes : — " The 

 larvae were much darker and redder than a brood I had reared to 

 moderate size the year previous, which were much more nearly like 

 the pale-greyish variety of the larva of crepuscularia. Probably the 

 larvie of hiundularia vary as much as do those of that species." Now, 

 in 1871, Mr. Porritt had described (E. M. M., vol. viii., p. 209), the 

 larva of T. crcpuficidaria, and, at the conclusion of his description, 

 adds the following : - " At the time that these larvae were changing to 

 pupae, I was taking the perfect insect of T. hiundularia at large." Here, 

 then, is an entomologist, who has bred both insects from larvae, 

 entirely supporting the view that they are distinct species. They had 

 distinct life-cycles, they bred true, and, in short, fulfilled the condi- 

 tions Avhich we usually require of species. 



My article (Entom., xix., pp. 98-101), previously referred to, 

 formed the basis of a series of articles. Mr. Adkin (Ihid, pp. 158-159) 

 supported the contention for two species by adducing evidence as to 



