March, 1902,] SeIFERT : NORTH AMERICAN ARCTIID^E. 5 



in irregular patches on the undersides of leaves which the larvae never 

 will touch (eggs oi A. vittata on underside of \^z.i o{ Ailanthus glan- 

 diilosa shoot), on pieces of wood, paper and other objects or are scat- 

 tered or in clusters on the bare ground. The eggs are not fastened 

 tightly, but are easily removed. 



Though all Arctiidfe are more or less polyphagous, the forms be- 

 longing to this group are inclined to prefer Tanixac-iim and Plantago 

 major to any other herb. The color of the eggs of all the species is 

 yellowish-white or pale straw color, rather bright with fine reticulations, 

 with naked eye they appear smooth ; they have the shape of blunt 

 cones with shallow bases. The width of the eggs of nais at base is 

 about 0.7 mm. and from vertex to base 0.6 mm. A sound, normal 

 female deposits at least 500 eggs. Of the three species occurring in 

 the vicinity of New York City, A. nais prefers the dry, scanty hill- 

 sides and pastures ; A. phalerata meadows, even damp ones, where 

 on sunny fall days the larvae may be found basking in the morning sun 

 on the branchlets of asters, etc.; A. vittata seems to be more in- 

 clined to frequent the grassy borders of woods, or rich forest lawns and 

 meadows. 



Arctla nais, on account of its habits, is the most common species 

 near New York. The larva in all its stages has been described by G. 

 H. French (Papilio, II, p. 179), but when reared in large numbers 

 and of different broods the variability of the larvae is striking, and in 

 some individuals where the typical pale dorsal band is obscured or 

 entirely obliterated, they can not be distinguished with certainty from 

 some of the varieties of the other species. 



To obtain some information about the variations of^. //«/> and 

 its larva, numerous broods were reared from May to September and 

 even during winter. (Eggs obtained December 3d and 4th, imagines 

 from March 17th; larvse fed with cultivated Ciilioriiim endivia.') 



The larvae after fourth moult attain in general their specific brown to 

 blackish color, the dorsal stripe often obscured but traceable. Achiev- 

 ing after sixth moult their maturity, they vary from yellowish-brown 

 to dull walnut, and from rich seal-brown to velvety black. The dorsal 

 stripe changes with individuals of the same brood from dusky white to 

 nankeen and flesh-color to reddish. T\\t stripe is often obscured on 

 the thoracic and the terminal segments, sometimes only observable on 

 the anterior of segments or not traceable at all. The color of the 

 bristles varies according to the ground color, but those directed from 



