146 



EUCHCETES COLLARIS, Fitch. 



Larva. (After 2d moult,) 



Body color, greenish-white. Head, slightly testaceous. The body 

 is covered with very long, sordid, white hairs, those of the anterior 

 portion the longest. A darker dorsal line, contrasting with the white 

 ground-color. 



Length, 8 mm. 



(After 3d moult.) 



The body has now become a clearer white, and the hairs, are dis- 

 posed more in the form of tubercular , tufts, and not irregularly, as in 

 the previous stages, the segments being marked by a deeper shade. 



Length 12 mm. 



(After 4th moult.) 



Wholly sordid white; the hairs now plainly disposed on pale tuber- 

 cles, each bearing a large tuft of hairs, which are cream-white at 

 their base, slightly stained with dusky at their tips. 



Length, 20 mm. 



(After 5th moult.) 



Head pale, testaceous. The hairs have now become pale mouse 

 color, varying in some individuals to a darker shade. The body color 

 and that of the legs are now dull greenish-white. 



Length, 28-30 mm. 



Food Plants: 



Asclepias, of several species; and Apocynum cannabinum. The larvae 

 feed only at night, hiding themselves during the day at the foot of their 

 food plant. 



Imago. Palpi, fore coxae, abdomen above, part of thorax, a costal 

 streak continued to the apex, and the costal edge of secondaries be- 

 neath, bright buff. The abdomen has three rows of black spots, those 

 of the dorsum the largest. The wings are pure white above, rather 

 acute at the apex; the primaries with a sub-costal, lead-colored shade 

 beneath, not reaching to the apex. The abdominal spots are occasion- 

 ally almost obsolete. 



Exp. wings, ,3, 35 mm. $, 42 mm. 



EuCHCETES YOSEMITE, n. Sp. 



Wings pure white above and below, except a buff shade on the 

 costa of primaries, not extenditig beyond the basal third, and a very 

 slight lead-colored sub-costal shade beneath. Costal edge of second- 

 aries, crea7n white. Abdomen cream-white, with the posterior edges 

 of the segments pale buff. Dorsal black spots quite conspicuous. 

 Otherwise, as in E. collaris 



Exp, wings, ($', 45 mm. $ , 48 mm. 



From several examples taken by myself in the Yosemite Valley, Cali- 

 fornia, 



