52 PROCEEDINGS OF THE NATIONAL MUSEUM. 



not in the least conic. The sexual pieces are also stron.yly alike in 

 both. They are oblong, the tip diagonal, while the clasi)er is of mod- 

 erate length and only a little curved. Twenty males and sixteen 

 females have been compared. 



LARVA. 



DiMMocK, Psyche, IV, p. 274.— Packard, Fifth Kept. IT. S. Ent. Oomm., 1890, 

 p. 498 (sp. 42, birch ins.); Ibid., p. 626 (hasfnUfera). — Edwauds and Elliot, 

 , Bull. Am. Mus. Nat. Hist., 1892, IV, p. 77. 



Stage L — Colorless, whitish, the food showing green. Hairs from 

 warts, long, silky white, mixed with a few black ones from warts I on 

 joints 3, 5, 7, and 12. Head bilobed, whitish, eyes black, mouth biowii ; 

 width, 0.7 mm. 



Stage II. — Head shining black with two concave white bands close 

 to the clypeus and connected above it by a cross-bar; a white mark 

 above ocelli, another behind; clypeus greenish centrally, mouth parts 

 pale; width, 1.2 mm. Hair long, curved, soft, white, with long, distinct, 

 single black pencils from tubercle I on joints 5, 7, and 12. Warts cou- 

 colorous, body whitish, a slight irregular black marking subdorsally. 



Stage III. — Head entirely black; width, 1.8 mm. Body as in the 

 mature larva, but only partly black, being spotted and streaked with 

 yellow, especially substigmatnlly. Primary hairs from distinct pale 

 warts, IV behind the spiracle, V and VI small; hairs long, barbuled. 

 Secondary hairs shorter, most numerous dorsally. Primary hairs all 

 white except the black pencils; secondary hair yellowish, shading to 

 tleshy brown on the back. 



Stage IT. — As before, the body blacker, very black in the incisures. 

 Secondary hair abundant, the black pencils long. Primary hairs stiff 

 and pale, radiating from the warts. Width of head, 2.4 mm. The 

 appearance of segmentary bauds of hair is heightened by the pale color 

 of the center of the segments contrasting with the black incisures. 

 Thoracic feet and venter black'. 



Stage V. — Like the mature larva; width of head, 3.6 mm. Lateral 

 hair all fleshy brown except stiginatally and subventrally, where it is 

 yellowish. Body all black except on the folds where the hair is very 

 thick and there it is pale yellow, ^o continuous yellow substigmatal 

 band. A narrow, faint, yellowish dorsal line of hairs. 



Stage VI, — Head black, the lobes separated by a vertical notch; 

 width, 4.5 mm. to 5 mm., line above labrum white. Body black, densely'- 

 covered with secondary hairs, except rather broadly in the incisures, 

 forming bands of short hair, obscuring the body except laterally where 

 it is much thinner; slightly keeled along the dorsal line. Hair light 

 yellowish on the sides, shading into fleshy brown on the back. On 

 joints 5, 7, and 12 a single erect black pencil, twice as long as the other 

 hair, yet relatively shorter than in the previous stage. A few long 

 white hairs from the extremities. A faint yellowish Irregular substig- 



