174 



americanum, with which it has long been confounded, and from which it 

 differs chiefly and ahnost exclusively in the general color. The former 

 {americanum) is more deeply and closely punctured about the head than the 

 latter. In the former the frontal costa, besides the smaller punctures, has, 

 along each margin, a row of regularly-spaced, large, black punctures, which 

 are wanting or less distinct in the latter. The spots of the latter are scarcely 

 as large and paler than in the fotmer. 



Color. — Yellow or brownish-yellow. Face yellow ; occiput pale-brown. 

 Dorsum of the pronotum light-brown; the dorsal stripe dim, and sometimes, 

 especially in the male, absent. Sides of the pronotum yellow; a dusky spot 

 in the middle, with a yellow stripe through it. Wings transparent-yellow at 

 the base ; veins of the apex and of tiie anterior portions black. Abdomen 

 greenish-yellow. Legs bright-yellow ; femora reddish above. 



Dimensions. — 9 Length, 2 inches; elytra, 1.95 inches. $ Length, 1.6 

 inches; elytra, 1.74 inches; posterior femora, 1 inch; posterior tibiae, 0.9 

 inch. 



Southern Illinois, Kansas, Tennessee (Thomas). 



A. ob!!iCuruui, Burm., Handb. Ent, II, 632. 



Syn., Oryllus obscurus, Fabr., Eut. Syst., suppl., 191. — Figd. Glov. Ills. Ent. 

 Orth., PI. V, Fig. 12. 



Female. — Body large, robust. Vertex hexagonal, bordered behind by a 

 transverse line running from the upper canthus of one eye to that of the 



are nearly exactly alike, but the general or ground color is different; and a close 

 liersoual observation of the two in Illiuois, for several years, inclines me to consider them 

 as distinct species. One always appears in the spring, April or May; the other never 

 earlier than the middle of July. And from specimens received from Tennessee and 

 Kansas, I am satisfied the same thing is true there, and it is, as I know from personal 

 observation, true in the District of Columbia. The two species also difl'er in appear- 

 ance when on the wing ; the A. americanum having the appearance and bright silvery 

 wings of the Calopteims spretus, while the other has not. 



De Geer (Mem. Ins., Ill, PL 40, Fig. 8) figures probably a specimen of my 

 ambiguum, which he names A. flavo-faticiatum ; but Serville's descrii)tion applies to 

 another species. Olivier's A. vittatum, which he makes synonymous with De Geer's 

 species, is also a difit'ereut insect (Encyc. Method. Ins. VI, 221). De Haau (Bijdr. Kenn. 

 Orthop., 113), who received specimens from Tennessee, undoubtedly of my ambiffuum, 

 says that A. carneii)es, Serv., is but a \'ariety of A. flavo-fasciaticin. Westwood, in his 

 edition of Drury, gives the name Locusta tartaricus to his figure, thus identifying it 

 with Grylhis tartaricun, Linn., one of the destructive oriental species. 



In this state of confusion, I have concluded to give a name to the yellow species, 

 us it does not clearly appear to have been distinguished from the A. americanum. 



