158 THE CANADIAN ENTOMOLOGIST. 



surprised how it could be possible for certain species to run through all 

 their transformations in so short a time. 



R. McLachlan, in his paper on the insects of Grinnell Land (Journ. 

 Linil Soc, Zoology, vol. xiv.), refers to the difficulties which the shortness 

 of the summer interposes to the development of insects, and intimates his 

 suspicion that a development which would with us take place in a single 

 summer would there require several summers. 



The correctness of this suspicion has been completely established by 

 the interesting observations on species of Lepidoptera in South Waranger, 

 in latitude 69° 40', made by G. Sandberg. He was successful in watching 

 the development of some extreme Northern species from the egg. 



Let us take as an example Qineis Bore, Schn., a true hyperborean 

 butterfly, which has never been found outside the Arctic circle*, and even 

 there only occurs in places which bear a truly Arctic stamp. 



The imago flies from the middle of June onwards, and lays its eggs 

 on various species of grass. The eggs are hatched the same summer ; 

 the larva hibernates below the surface of the earth, feeds and grows all 

 through the following summer, but does not succeed in attaining its full 

 size ; it then hibernates a second time, and does not assume the pupa 

 state till the spring of the following year. 



The pupa, which in the allied forms in more southern localities is 

 freely suspended in the air to a grass-stem or some similar object, here 

 reposes in the earth, which in so inclement a climate must evidently be a 

 great advantage. 



The butterfly escapes from the pupa-skin after an interval of from 

 5 — 6 weeks, a period of unusual length for a diurnal Lepidopteron. In 

 more southern lands the pupal repose of butterflies in summer rarely 

 exceeds a fortnight. Hence, the entire metamorphosis is more tedious 

 than in more temperate regions. 



By these and other observations, Sandberg shows that one Arctic 

 summer, in latitude 70°, does not suffice for the development of many 

 Lepidoptera, but that two or more summers are required for the purpose. 



If, therefore, more than one summer is needful for the development of 

 Lepidoptera, it appears to me even more certain that Humble-bees must 



* Mr. W. H. Edwards informs us that Mr. David Bruce has taken Chionobas 

 Taygett Hub., which is syn. of Ociicis Bore Sch., in Colorado^ on summits, at high 

 elevation. Mr. Edwards' Catalogue, No. 304, says Taygctc Hub. = Bootes Bd., and 

 .Staudinger's Cat. sa.ys Bore Sch. is the same as these, that is, it is all one species. — Ed. 

 C. E. 



