66 TRANS. ST. LOUIS ACAD. SCIENCE. 



with luteous. Ovipositor dull luteous, each plate with a narrow blackish 

 vitta in its middle; sheaths black, sanguineous on their superior base. Z^e£^s 

 blue-black; tarsi blackish. Wing's clouded with fuliginous, opaque blue- 

 black along the costal margin, the postcostal space mostly hyaline. Veins, 

 costa and stigma black. Hind wings paler, the hyaline space extending on 

 to the disk. The last submarginal cross-vein very rarely (25) with a stump 

 of a vein springing from it at the curve. Length $ •35-'40 (.45 Say) inch. 

 Front wing 5 .38-.40 inch. 



(^ Differs from $ only as follows : — i. The antennae are i (not |) as long 

 as the body, and the hairs on the last joint are | its breadth. 2. The scutel 

 is full as often black as sanguineous. 3. It is often the case that only the 

 extreme anterior angle of the collare is black. 4. From 2 to 6 of the basal 

 oints of the dorsum of the abdomen are often black (5 (^ out of 9 (^) except 

 laterally, and the last ventral is never luteous, but often tipped more or less 

 widely with black. 5. The wings are much paler, the costa only blue-black. 

 Length (^ .27-.30 inch. Front wing ^ .28-.30 inch. 



Nine c? , twenty-one ? . A very handsome species. Say describes 

 the ? only, and from a single specimen with mutilated legs. He 

 makes the ground-color to be "fulvous" or "reddish-yellow," in- 

 stead of sanguineous as in all my c? ? ; but his specimen was per- 

 haps alcoholic. He gives no habitat for the species. It is singular 

 that this insect should vary in both sexes, so as sometimes to lack 

 the very character from which Say's name is derived, viz. the red 

 scutel. His ? was .05 inch longer than any of mine. In i c? i ? 

 with black scutel and i ? with sanguineous scutel the 2d recur- 

 rent vein coincides with the 2d submarginal cross-vein, and all the 

 intermediate grades occur between this and the normal structure. 

 The same thing occurs also sometimes in dulciaria^ Say, and ca/- 

 canea^ Say, as shown below. As it is upon this character that the 

 genus Scobina, St. Farg. & Serv., appears to have been exclusively 

 established, it must in that case be suppressed. (See Brull6 Hy- 

 men, p. 669.) 



Hylotoma COCClnea, (•''.'') Fabr. $. — Differs from the above $ only as fol- 

 lows : — I. The head, except the tips of the mandibles, the palpi, and some- 

 times the labrum, which are dusky, and the eyes and antennae, which are 

 black, is sanguineous. 2. The clypeus is scarcely rugose. 3. The antennae 

 are only J as long as the body. 4. The entire thorax is bright sanguineous, 

 except the tegulae and a mesonotal spot above the origin of each one of the 

 4 wings, which are black, and the cross-carinae and basal plates of the me- 

 tanotum, which are obfuscated. 5. The hind coxae, except at tip, are san- 

 guineous; the rest of the legs black. 6. The hind wings are as dark as the 

 front ones, except on the costa; and in both wings of i $ the last submar- 

 ginal cross-vein has a stump of a vein springing from it. Length $ .43-.45 

 inch. Front wing $ •38-.39 inch. 



