I20 



•seventy-five specimens of this insect (which are in the hands of 

 Dr. Hagen, of Cambridge) and to raise it from the larva. 



We first saw the butterfly on the wing at Umatilla, Oregon, 

 on the south bank of the Columbia River, June 24th, capturing 

 thirty-six specimens from flowers of a species of evening prim- 

 rose or fluttering round a species of Artemisia. On the north 

 bank of the river, being then in Washington Territory, we took as 

 many more on June 26th, from thistle heads, and I saw a female 

 deposit one ^g^ on Artcinisa. On July 4th, Mr. Henshaw found 

 one half-grown larva on Daucus, at Nelson's, about ten miles 

 north of Yakima City, and July 5th I found another, preparing 

 to pupate on Artemisia', butnot the same species of plant on which 

 I saw the &^^ laid. I was successful in raising a very fine example 

 from this larva. On July i6th and i8th the butterfly was either 

 seen or captured on the Yakima River, about half way to its junc- 

 tion with the Columbia, but it was quite rare. When at Spokane 

 Falls I saw a number of specimens collected by Mr. Ricksecker. 

 These localities show a wide range. They are all on the great 

 basaltic plateau which occupies the central portion of the Terri- 

 tory and is essentially the home of the Artemisias. 



The species is probably single brooded in this area. 



Description of tJie Larva. — Length about two inches. Horn 

 •orange-yellow, bifurcate. 



Entire larva pale yellowish-green, inclining to bluish round 

 the transverse markings and on the ventral parts. 



Head with two vertical, frontal black lines, divergent at their 

 lower ends, and a lateral vertical black line, with a black dot be- 

 tween each of the lines just above the mouth parts. 



Second segment with two transverse black lines, each with a 

 terminal black dot laterally, and at the horn opening a slender 

 transverse black line with three heavier longitudinal branches, 

 like the top of the capital letter T. A lateral flat dull yellow 

 tubercle. 



Third, a strong black transverse velvety black line, evenly cut 

 behind, with four indentations in front, each filled with a yellow 

 tubercle, with a black spot low down laterally, supplemented 

 above with a yellow tubercle. Posterior suture black. 



Segments four to twelve alike, except that the black mark- 

 ings gradually diminished in strength posteriorly ; sutures black 

 when the larva is extended. The yellow tubercles indenting the 

 black transverse line on segment three cut it up into five trans- 

 verse black spots, the lateral one on segment four being large, 

 the other similar ones smaller, linear and oblique ; below these is 

 a third yellow tubercle, followed by a linear black spot, so that 

 -each of these segments has a transverse series of seven black 

 spots, the dorsal one the largest, between which are three lateral 

 TOWS of yellow tubercles. 



