BEUTENMULLER, MONOGRAPH OF THE SESIIDiE. 295 



sects, 1877 ; Kellicott, Can. Ent. Vol. XIII, 1881, p. 7 ; ibid. Vol. XXIV, 1892, p. 46 ; 



Journ. Columbus. Hort. Soc. 1890, p. 61 ; Martin, 5th Rep. Nox. Ins. 111. (Thomas), 1880 



(1881), p. 108 ; Prairie Farmer, Apr. 5, 1890 ; Packard, Ins. Inj. For. and Sh. Trees (Bull. 



No. 7, U. S. Ent. Com. 1881, p. 106); 5th Rep. U. S. Ent. Com. 1890, p. 384; Bell & 



Reed, Can. Ent. Vol. XIII, 1881, p. 236 ; Grote, New Check List N. Am. Moths, 1882, 



p. 12 ; Saunders, Can. Ent. Vol. XIII, 1881, p. 69 ; ibid. Vol. XV, 1883, 187 ; Rep. Ent. 



Soc. Ont. 1881, p. 20 ; ibid. 1883 (1884), p. 12 ; Riley, Am. Nat. Vol. VII, 1874, p. 123 ; 



ibid. Vol. XV, 1881, p. 751 ; Reed, Can. Ent. Vol. XVI, 1884, p. 220 ; Rep. Ent. Soc. Ont. 



1884 (1885), p. 24 ; Harrington, Rep. Ent. Soc. Ont. 1887, p. 24 ; Weed, Am. Nat. Vol. 



XXIII, 1889, p. 1 108, pi. 43, fig. 5 ; Riley & Howard, Ins. Life, Vol. Ill, 1890, p. 161 ; 



Wiley, Insect Life, Vol. II, 1890, p. 251 ; Beutenmuller, Ann. N. Y. Acad. Sc. Vol. V, 



1890, p. 205 ; Lintner, Gardening, 1884, p. 56 ; Osborn, Orange Judd Farm. 1890, p. 261 ; 



Bruner, Rep. Neb. Hort. Soc. 1891, p. 151. 

 Sesia acerni Hulst, Bull. Brooklyn Ent. Soc. Vol. VI, 1883, p. 10 ; Smith, Cat. Ins. N. J. 1890, p. 



289 ; Lugger, Bull. 43, Agricul. Exp. St. Minn. 1895, p. 188, fig. ; 1st. Rep. Ent. Agri. Exp. 



St. Minn. 1895 (1896), p. 92, fig. ; Beutenmuller, Bull. Am. Mus. Nat. Hist. Vol. VIII, 



1896, p. 138 ; ibid. Vol. IX, 1897, p. 220 ; Bruner, Rep. Neb. Hort. Soc. 1894, p. 154. 

 Trochilium acericohim Germadius, Am. Nat. Vol. VIII, 1874, p. 57. 



Male. — Head, collar, and palpi orange, orbits white. Antennae brown black. Thorax above 

 and below yellow. Abdomen blue black more or less scaled with pale yellow, underside wholly 

 yellow. Anal tuft bright orange. Legs pale yellow, tibiae with a black band at the end. Fore wings 

 narrow, elongate, with narrow purplish borders more or less covered with pale yellow scales, outer 

 part of wings pale yellow between the veins, with indications of a broken band. Discal mark large 

 and deep black. Underside same as above. Hind wings transparent with the very narrow border 

 and fringes purplish brown, sometimes yellow at the apex ; underside similar to the upper, but with 

 the costa marked with yellow. 



Female. — Similar to the male. The margins of all the wings are darker in color and the hind 

 wings want the yellow at the apex. 



Expanse : Male and female, 22-25 mm. 



Habitat.— Canada, New England and Middle States, westward to Nebraska. 



Type : Lost. 



Larva. — " Head rounded, the clypeus triangular, the paraclypeal pieces rounded above, con- 

 stricted, shield-shaped ; lobes somewhat broadly touching ; pale testaceous, mouth between antennae 

 broadly black, sutures of clypeus brown ; lower posterocellus with a slight lens. Body moderate, 

 weakly annulate, the third annulet the highest ; feet sessile, the crochets small, well developed, and 

 normal, twelve to fourteen in a row. Somewhat flattened, subventral fold prominent. Whitish, the 

 shield lines not evident ; anal plate with a distinct tubercle each side tip and three other small ones, 

 respectively subdorsal, lateral, and on the posterior rim within the large one. Spiracles small, brown- 

 rimmed." (Dyar, MS.) 



This is one of the most common species and is sometimes exceedingly 

 destructive to different kinds of maples, especially the silver maple (Acer 

 dasycarpuni), the soft maple (Acer rubrum), ' and the sugar maple (Acer 

 sacchar intern). It also infests the mountain ash (Pyrus americand). The 

 female deposits her eggs in the roughened parts of the trunks and branches 

 or in wounded places. The larvae feed upon the inner portions and sap 

 wood, never penetrating into the solid wood. The excavations made by 

 the larvae are filled with its brown castings. When once established they 

 keep at the scar or wound year after year, thus preventing recovery and 



