406 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 



noticed early in August, but becomes fully fed by the first week in 

 September, my specimens transforming September 8, the chrysalis 

 euteriug the earth. I have also found it fully fed on the white birch 

 at Brunswick as early as August 10. It also feeds on the maple. 

 The moth appears in June in Maine late in May in southern New 

 England and New York. I have raised this moth in Maine from the 

 larch (pupating September 15), also from the Missouri currant, an orna- 

 mental shrub ; also from the apple, elm, cherry, and the aspen in Rhode 

 Island, though the willow is probably its native food-plant, as it occurs 

 in greatest abundance on that tree. Mr. Lintner states that the larva 

 feeds on the maple ; that the caterpillar entered the ground for pupa- 

 tion August 11, the moth emerging the latter part of May. (Ent. Contr. 

 iii, 166.) My specimens emerged in Providence May 13. The larva 

 found on the aspen is greenish and like a fresh aspen twig, with whitish 

 granulations, which are black on the tubercles. 



It is subject to the attacks of a species of Microgaster, seven larvae of 

 the latter making their exit from a caterpillar two thirds grown. The 

 following historical sketch of our knowledge of this insect is taken 

 from Mrs. Dimmock's article in Psyche, iv, p. 271. 



Amphidasys cognataria Gueu^e (Hist. Nat. d. Ins., 1857, V. 9, Uran. et Phal., v, i, 

 p. 208). Cramer (Bull. Brooklyn Eutom, Soc, Aug. 1883, v, 6, p. 48) briefly describes 

 the eggs of this species, of which about five hundred were deposited June 3. Bowles 

 (Can. Entoui., April, 1871, v, 3, p. 11-12) (Ana. Ropt. Entoiu. Soc. Ontario, 1871, p. 

 38-39) describes a variety of the larva which fed on " black currant " lEibes ?ni()rum'\, 

 and Goodell {op. cit., April, 1878, v, 10, p. 67) describes another variety which fed on 

 apple and pear. Lintner (Eutom. Coutrib., No. 3, 1874, p. 166) briefly describes the 

 larva, giving Acer as food-plant, aud Packard (Guide Study Ins., 1869, p. 322) gives 

 a few notes on the larva, which he states feeds upon Ribes aureum, R. ?gros8uIaria, 

 and Spiraea Uomenlosa. Pilate (Papilio, May, 1882, V, 2, p. 71) gives "honey-locust" 

 {Gleditschia triacanthos) as food-plant. Lintuer (Entom. Contrib. [No. 1], 1869, p. 

 64) gives plum as food-plant. To the above food-plants may be added Betula alba, 

 B. lenta, Castanea vesca, Salix, and Spircea sorMfoUa. The larva varies from pea-green 

 to brownish gray or even brownish black in general color ; as far as noticed the greeu 

 form is from Bibes, Salix, and Spircea, while those from apple exhibit all the color 

 variations ; on Betula aud Castanea the larvae are gray. Similar variations have been 

 noticed in the larvic of Amphidasys hetiilaria, a European species. The larvae often 

 rest in a partially twisted position, with their rigid bodies at a considerable angle 

 from the stem to which they cling, thus imitating very closely twigs and petioles. 

 The larvae are common in New England in July and August ; they pupate from the 

 latter part of July to September, the pupa hibernating under leaves aud rubbish. 



Young larva. — Body cylindrical; segments much wrinkled above, but not tuber- 

 culated. Head large aud square in front ; vertex very deeply notched, each tubercle 

 acute above, conical aud rough, granulated ; clypeal sutures deeply impressed. 

 Prothoracic segment above broad and flat, transversely oblong, with a slight low 

 tubercle on each side in front, making the cervical shield angular in front. A 

 pair of remote but conspicuous though small round white patches on mesothoracic 

 and the seven following segments. Fifth abdominal segment with a small thick 

 tubercle low down on the side. Aual legs large, broad, and flaring. General color 

 rust-red. Length, 15""". 



Larva before the last molt.— With the characters of the adult larva ; salmon red 

 Leugth, 35"™. 



