152 ARCTIAD^. 



arranged in a trapezoid ; hairs in general pale yellowish ; legs 

 blackish. 



Stage 3. Body entirely concealed by hair arranged in dense 

 bunches of unequal length, a few long white hairs from Ist and 

 3rd somites, the other hairs straw-yellow, except a series of eight 

 double median dorsal black tufts, the first and last much larger ; 

 a pair of lateral thick black tufts on somites 4 and 11, the tubercles 

 from which they arise being surrounded with black, a broad black 

 lateral interrupted band connecting these patches. 



Mature : Body blackish, densely covered with deep lemon-yellow 

 hairs, longer on the sides ; head black, clypeus and antennae whitish, 

 the head with sparse unequal black hair ; abdominal somites with a 

 series of eight double dorsal black tufts, the 1st higher and narrower, 

 the 7th shorter and wider ; somites 4 and 10 with lateral black 

 tufts ; thoracic somites with six long slender w^hite tufts, 7th and 

 8th somites with three pairs of similar whitish tufts. Food-plant, 

 Poplar, Maple, &c. 



Cocoon thin, of silk and hair, velvety. 



Pupa. Thorax and abdomen enlarged centrally, with a depression 

 between them ; ventral side straight, flattened : ends obtuse ; 

 abdominal segments fixed ; cremaster of spiny hair. 



Subsp. 1. angulifera, Wlk. Lord's Nat. in Vaucouv. ii. p. .355 (1866) : Kirby, 

 Cat. Het. p. 208. 

 Halesidota alni, H. Edw. P. Calif. Acad. vii. p. 129 (1877). 



Imago similar. 



Larva. Dyar, Psyche, vi. p. 32o. 



Young : With tufts of red, instead of black, hair. 



Mature : Head black ; bases of antennte, labium, and a line below 

 clypeus yellow ; body black, mottled with yellowish ; warts with 

 spreading tufts of feathery hair, on somites 1-5 and 9-12 deep 

 black, on somites 6-8 orange-ochreous, the black parts with long 

 slender white pencils on somites 2, 3 from warts ii.-v., on somite 4 

 from warts i.-v., on somite 5 single hairs from warts iii., iv., on 

 somite 9 single hairs from warts ii.-iv., on somite 10 from warts ii., 

 iii., v., on somite 11 from warts i., ii., on somite 12 from the large 

 and lateral warts. Food-plants, Salix and Alnus. 



Hah. British Columbia {Lord), 1 S type, Fraser Ii. {St. John), 

 1 c5' ; VANCorvER I. {Danhy, J. J. Wall^er), 4 (^ , 4 $ ; California, 

 Sierra Nevada. 



Subsp. 2. agassizi, Pack. Proc. Ent. Soc. Phil. iii. p. 128 (1864); Kirby, 

 Cat. Het. p. 207. 

 Halesidota calif ornica, Wlk. xxxi. 311 (1864). 

 Phegoptera salicis, Boisd. Ann. Soc. Ent. Beige, xii. p. 81 (1869). 

 Colour rather deeper ; the markings sufi'used by the ground- 

 colour, often more or less obsolescent, but leaving a dark discoidal 

 spot. 



Rah. California coast-region, 2 J , 2 $ , type, Grotc Coll. 1 d . 



