1909] American species of Scolioenurinae 261 



Genera of Scolioneurinae. 



a. Front wings with the radial cross-vein and the free part of R4 interstitial; 



the antennal furrows practically continuous throughout 



Scolioneura Knw. 

 aa. Front wings with the radial cross-vein and the free part of R., widely sepa- 

 rated ; the antennal furrows broadly interrupted on the middle of the 

 front, 

 b. Antennae with the second segment distinctly longer than broad; the 

 first and second segments together as long as or longer than the 



third Parabates n. gen. 



bb. Antennae with the second segment annular, broader than long; the 

 first and second segments together shorter than the third, 

 c. Eyes with their inner margins straight and parallel, not converg- 

 ing below; the front distinctly wider than high 



Polybates n. gen. 

 cc. Eyes with their inner margins uniformly convex and converging 

 below; the front not as wide as high, 

 d. Front wings with the free part of R4 and the radial cross- vein 



inclined at different angles Metallus Forbes 



dd. Front wings with the free part of R^ and the radial cross-vein 



inclined at approximately the same angle 



Entodecta Knw. 



Scolioneura Knw. 



Head transverse, the front distinctly broader than high; 

 the inner margin of the e^^es straight and parallel, the eyes 

 not converging below; the antennal furrow^s deep and distinct, 

 practically continuous from the antennal fovea to the occiput; 

 the clypeus squarely truncate, distinctly more than half as wide 

 at apex as at base; the antennae long and filliform, the second 

 segment shorter than the first, broader than long, globular, not 

 annular, the first and second segments together shorter than the 

 third; front wings with the free part of R4 and the radial cross- 

 vein interstitial and inclined at the same angle; the free part of 

 M^+Cuj received at or beyond the middle of the cell ist A + 

 2nd 2nd A; media strongly angular at the point of separation 

 of Mi + 2 and M3+4. Type Tenthredo betuleti Klg. 



This generic name as here used is restricted to those species 

 in which the radial cross- vein and the free part of R^ is interstitial. 

 The generic diagnosis is based on a specimen of the type species 

 identified by Dr. Fr. W. Konow. For a further discussion of 

 the characters used for this genus see under Entodecta. 



Scolioneura populi Marl. 



Body whitish with the following parts black: the antennal fur- 

 rows, the antennal fovea, a spot around the anterior ocellus, a trans- 

 verse band on the postocular area, the antennae beyond the first seg- 

 ment, a spot on the median and lateral lobes of the mesonotum, the 

 scutellum, the metathorax, the apex of the pectus, the abdomen above. 



