June, I902.] SeIFERT: NoRTH AMERICAN ARCTIID/E. 83 



near the remnants of the iridescent membranes. The larvee were 

 reared to maturity on Taraxacum tayaxacnin and Plantago major, with 

 occasionally some lettuce leaves. Structurally they do not deviate 

 from the other larvae of the group, the arrangement and development 

 of warts and bristles being normal. (G. H. French, Papilio, Vol. II, 

 p. 176, 1882; A. Gibson, Can. Ent., Vol. XXXII, p. 369, 1900.) 



Stage I. — The newly hatched larvcC are semitransparent, of a sordid 

 yello\vish-white with black warts. The head jet black, sparsely hairy ; 

 clypeus, epistoma, and mouth parts sordid whitish, the latter tipped 

 with brown. Hairs emitted singly from the warts, rather long but 

 even, except a few long projecting hairs from the anal segment ; legs 

 concolorous with body. 



The singular variability of the young larva; during growth in the 

 first stage, which makes them appear all shades from amber color and 

 smoky greenish to sordid white, seems to have its cause in the irregu- 

 lar accumulation of pigment around the bases of the warts. 



Stage II. — Right after moulting the larva; attain an average length 

 of 3.5 mm. when resting, measured from head to anal feet. Width of 

 head 0.6 mm. A white dorsal stripe, narrow on thoracic segments, 

 widening and attenuated in the middle of abdominal somites, and the 

 stellate uneven bristles on the warts are the most important features 

 obtained at this stage. The opaque white dorsal stripe is only partly 

 present on the prothoracic segment ; narrow and even on second and 

 third thoracic and anal segments ; the abdominal somites, except 

 the last one, have the stripe rather narrowed anteriorly owing to its 

 evading the bases of the minute subdorsal warts (i), but extending 

 posteriorly to the large subdorsal ones (ii) (Dyar, Entom. Amer., Vol. 

 VI, p. 74, 1890) and narrowing again near suture of somite. The 

 bases of warts i and ii are brownish, the brown shades spreading and 

 uniting to form a brownish band or area, less developed on the 

 thoracic segments ; below this lateral area the color is uniformly sooty 

 grayish, amber, or dusky green, only the summits of the warts black- 

 ish, their bases dusky orange. The hair on anterior warts of first seg- 

 ment is turned over the upper part of head. 



Stage III. — After the second moult the larvae attain an average 

 length of 7.5 mm. when resting; width of head 0.9 mm. No ma- 

 terial changes have taken place, but the colors are more intensified. 

 Subdorsal warts bright black from their bases. The whole space be- 

 low lateral area dusky orange, sutures of suprastigmatal region more or 



