THE CANADIAN ENTOMOLOGIST. 229 



Prof. French. These were of the earliest butterflies, and I expected to 

 raise them to imago the same summer. 



On 2nd and 3rd July, all these larv?e passed ist moult ; on 6th July, 

 two passed 2nd moult; on loth or nth, one passed 3rd moult. On 27th 

 July, the three survivors had been lethargic for about a week, as I re- 

 corded. Later, I sent these to Clifton Springs. So that larvae from the 

 earliest flight of the butterflies, as far as observed, hibernate, as do the 

 larvae of the later flight, and all would produce butterflies in spring. 

 How comes it then that there is the appearance of a second brood of the 

 butterfly in late summer, or August ? Apparently one brood flies in June, 

 another in August, though fresh butterflies are also found in July, and one 

 would expect eggs of the June brood to produce the August butterflies. 

 The explanation I conceive may be this : in June, the butterflies from the 

 lower elevations first come from pupae, in July from higher elevations, 

 and in August from the highest of all, and a constant stream of fresh 

 butterflies is kept up from higher to lower elevations. Mr. David Bruce 

 has collected several seasons in Colorado at every altitude, and in 1887, 

 particularly, his attention was directed to the habits of Alexandra, and 

 this is what he writes 22nd Sept , 1887 : "I think my notes and the speci- 

 mens sent will satisfy you that there can be but one brood annually of 

 Alexandra. This species is a powerful flier and takes very long flights, 

 and in the narrow canons will fly along the side of the trail or stream 

 down hill for miles. Even Colias Meadii, when it once gets in the canons, 

 will follow the track, and I have found several at Webster, 9000 feet, and 

 below it, though their proper habitat is 2000 or 3000 feet higher." Alex- 

 andra is found at various elevations- from 6000 to 10,000 feet. 



As to C. Edwardsii and its relationship to Alexandra ; I have of late 

 years thought it probable that the former might be a dimorphic form of 

 the other. But if there is but one annual brood of Alexandra, that view 

 is not tenable. Edwardsii was named by Dr. Behr, from examples taken 

 in Nevada, and was first described in- vol. i, But. N. A., in 1869. At 

 that time very few examples were known, and the same is true as to 

 Alexandra, originally described in 1863. It was not till Mr. Mead col- 

 lected in the summer of 1S71, in Colorado, that Alexandra became better 

 known. Since then a vast deal of collecting has been done in Colorado, 

 and Alexandra is found in every collection. Edwardsii yet differed 

 from Alexafidra, as known up to 1869, in the shape of the wings, these 

 being narrow, the fore wings pointed apically, the hind margins incurved ; 



