54 THE CANADIAN ENTOMOLOGIST. 



Mr. Fletcher, that Macounii (from Nepigon), has that habit. C £rucei, 

 allied to Semidea, has with me reached adult larva the first season, and 

 probably the Colorado Semidea would behave the same way. But the 

 conditions in Colorado, even on the highest peaics, are not so trying to 

 insect life as on the White Mountains. 



8. Food-plants of certain Colias larvse. 



The larvae of C. Scudde?'ii and Nastes feed on willow. I found those 

 of the former would not touch white clover (or any clover) which the 

 other alpine species, Meadii, E/is. Alexandra, eat ; and it occurred to 

 me to try willow. I gave them tender leaves of weeping willow, and they 

 took to it at once. Mr. Bruce saw the female laying on a species of 

 Vaccinium at Hall Valley, caught and confined her and got twenty eggs. 

 He told me that he had often noticed the females flying in and out the 

 dwarf willows as if laying eggs. I got the larvae past second moult and 

 then lost the whole of them. 



As to Nastes, Mr. Bean, at Laggan, wrote :— '• The larvae feed on 

 willow, and not mountain willow only, but from the banks of the Bow. I 

 don't find any eating Vaccinium, but a lot on Hedysarum are doing 

 well." 



Messrs. Fletcher and Scudder obtained eggs of C. Interior, at 

 Nepigon, and distributed part of them. I had fifteen or twenty, and they 

 hatched ; but the larvae refused white clover and several other sorts of 

 leaf which I tried them on, and all starved. I did not then know that 

 willow was a food-plant of any Colias. Neither of the gentlemen named 

 had better success than I had. Mr, Bean told me later that the food- 

 plant of Interior was Vaccinium. 



9. Colias Meadii and £lis. 



These species, in their early stages, cannot be separated. The larvie 

 are precisely alike, even under the glass, so far as I have been able to 

 discover, and they differ in appearance from all other larvie of the genus 

 observed by me, being thickly coated with short, black bristles, or stiff 

 hairs. There is a basal stripe of pure white, with no red in it, and a sub- 

 dorsal stripe of yellow-white. Many of the imagos of Meadii taken at 

 Hall Valley and on the higher levels, in September and October, are very 

 pale coloured (as to both the orange and black), and are undisiinguish- 



