THE STATE ENTOMOLOGIST. 



51 



name has the priority, but I introduce Mr. Walsh's original descrip- 

 tion of the fly and likewise the very same figure (Fig. 17) which he 

 used to illustrate it. 



Exoiista leucanice — Length, .25 to .40 inches, or from 6 to 

 10 millimetres, the females not exceeding .30 inch. Face sil- 

 very, with lateral blnck hairs only on the cheeks, at the top of 

 which is a black bristle. Front, golden-olive, with a black cen- 

 tral stripe, and lateral black convergent hairs. Occiput, dusky. 

 VLabium, brown, with yellowish hair. Maxipalps, rufous. Eyes, 

 cinnamon-brown, covered with very short dense whitish hair. 

 Antenna}, two basal joints, black, with black hairs; third joint, 

 flattened, dusky, and from two and a half to three times the 

 length of the second joint; seta, black. The entire hinder part 

 of the head covered with dense whitish hair. Thorax glabrous, bluish-gray, lighter at the side, 

 with four irregular black vittae, and black hairs and bristles. Scutel, reddish-brown, whitish be- 

 hind, glabrous, with black hairs and bristles. Pectus, black, glabrous, with hairs and lateral 

 bristles. Legs, black, hairy ; thighs, dark cinereous beneath ; pulvilli, cinereous. Wings, hyaline ; 

 aervures, brownish; alula;, opaque greenish-white. Abdomen, first joint black ; second and third, 

 opalescent in the middle with black and gray, and at the sides with rufous and gray ; last joint, 

 rufous, slightl}' opalescent at the base with gray ; all with black hairs and lateral bristles. Be- 

 neath, the first joint is black, the others black, margined with rufous, all with black hairs. In the 

 male the space between the eyes at the occiput is one-seventh of the transverse diameter of the 

 head ; in the female it is one-fourth. The colors of the abdomen sometimes " grease" and fade 

 in the dried specimen. 



Bred fifty-four specimens from about the same number of Army-worms. Described from eight 

 males and six females. Two species, similarly marked with rufous, but generally distinct, occur 

 at Rock Island. 



Mr. Kirkpatrick also described on the same page of the Ohio 

 Report for 18'iO, another species (?) to which he gave the name of Osten 

 Sachenii. But upon the very face of it, this proves to be but a smaller 

 specimen of his leucanim; for the characters on which he would build 

 this other species, are none of them constant. He says it differs from 

 leucanice in its smaller size ; in the gray bands on the abdomen not 

 being so distinct ; in some little variation in the position of the brown, 

 and in the pulvitt[i]ce being more distinctly gray. Now leucanice va- 

 ries from 0.25 to 0.40 inch in length ; the brown on the abdomen is 

 opalescent and varies; the pulvilli and gray abdominal markings 

 vary far more in depth of shade than there set forth, and the abdo- 

 men in fact, if the least greasy, often loses all trace of gray. 



The Yellow-tailed Tachina Fly, QExoris- 

 ta Havicauda^ N. Sp.) — We have another spe- 

 cies in Missouri however, which may be call- 

 ed the Yellow-tailed Tachina Fly, and which 

 differs so notably from the Red-tailed species 

 that it may be recognized even on the wing. 

 It is almost twice as large, and the head in- 

 stead of being narrower than the thorax as in 

 leucanice, is broader. Its flight is also more 

 vigorous and its buzz twice as loud, I represent this species at Fig- 

 ure 18, and draw up the following description for the scientific 

 reader: 



Exoriitaflavicauda, N. Sp. — Length, 0.35 to 0.50 inch. Head broader than thorax; face, sil- 

 very-white, the cheeks inclining to yellow, with lateral black hairs extending to near the base of 



