the large and small Cabbage Butterjlies. 243 



interesting Blustrations of Entomology, now in the course of 

 publication. It yet remains to be seen, however, whether, in 

 the judgment of entomologists in general, these Early Whites 

 (as they are termed) will eventually maintain their place as 

 genuine and distinct species ; and it is under the hope that 

 some accurate observer may be induced to institute experi- 

 ments with a view to set the question at rest, that I call your 

 attention to the subject. For myself, I may say that I have 

 not been unobservant of these insects for some years past, but 

 have more particularly attended to them during the spring and 

 summer of the present year ; and, as far as my observations 

 go, they lead me to the conclusion that P. Charicle« and Metr« 

 are mere varieties respectively of P. brassicae and rapae. P. 

 rapae is avowedly a very variable insect, and being too, as well as 

 P. brassicae, a most abundant species, there is consequently the 

 more scope — there are so many more chances—- for variation 

 to take place in the individuals. It must be admitted, indeed, 

 that when a small and perfectly immaculate specimen of P. 

 Metra is compared with a full-sized and strongly marked one 

 of P. rapae, the prima facie difference is so wide, that any one 

 would at once pronounce them distinct. But then, on the 

 other hand, we find that intermediate specimens occur, which, 

 presenting every possible shade and gradation of difference, 

 appear naturally to connect and identify the two extremes ; 

 and it would be next to impossible to decide, in many instances, 

 to which of the two these intermediate links should with 

 most propriety be referred. The same observations apply 

 also to the kindred species P. napi, the earliest spring speci- 

 mens of which are smaller than those of the summer brood, 

 paler in their markings above, and sometimes almost entirely 

 destitute of them ; and this species too, like P. brassicae and 

 rapae, is subject to endless variations. In the spring of the 

 present year I took many specimens of the pale varieties of all 

 three species (one of P. rapae so early as * March 18.), but 

 I could not observe that any of the paler specimens of either 

 kind occurred in the summer brood. In a note at the end of 

 the volume, Mr. Stephens states his opinion, that P. Chariclea 

 and P. Metra are neither of them double-brooded, as he once 

 supposed ; and hence, perhaps, he would draw an additional 

 argument in proof of their being distinct from P. brassicae and 



* This is the only instance I ever knew of any Papilio coming forth from 

 the chrysalis so early in the spring ; for although Vanessa To, Polychloros, 

 urticae, and C. album, and Gonepteryx rhamni are often to be seen on the 

 wing earlier in the month, and some of them occasionally in February or 

 even January, these vernal specimens, it must be remembered, are such as 

 have been produced in the preceding autumn, and have secreted themselves 

 dwing the winter in the whiged state. 



