122 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiii. 



transverse nervures or stumps of nervures; first abscissa of the radius straifrht, 

 perpendicular, forming with the second an acute right angle. 



Tribe I. Blacini. 

 2. Second abscissa of radius straight, not at all arcuate and forming with the trans- 

 verse cubitus almost a straight line; tibial spurs long; anal cell ?ioi divided. 



Tribe II. Orgiuni. 



Second abscissa of radius nhvaij.'^ more or less arcuate or curving slightly upwards 



and never forming" a straight line with the transverse cubitus; tibial spurs 



short; anal cell most frequently divided or with traces of stumps of veins, 



rarely normal Tribe III. Calvitini. 



Tribe I. BLACINI. 

 1900. Blacini, Tribe III, Ashmead, Smith's Insects of New Jersey, p. 690. 



The species falling in this tribe always have the second discoidal cell 

 open at the apex, the first abscissa of the radius is straight or perpen- 

 dicular and forms an acute angle with the second abscissa, while the 

 anal cell is never divided by a transverse nervure, the submedian vein 

 being without a trace of such a nervure. 



Five genera may he distinguished in this group, as follows: 



TABLE OF (iENERA. 



First discoidal cell sessile, the cubitus emerging from the parastigma 2 



First discoidal cell petiolate,the cubitus emerging from the basal nervure. 



(946) Pygostolus Haliday. 



2. Metathorax normal, the scutellum rounded or obtuse at apex, never toothed. 3 

 Metathorax with a very obtuse angular ridge toward apex, the hind angles of 



the posterior face toothed; scutellum triangular in male, acutely toothed 

 at apex (947) (ioniocormus Forster. 



3. Submedian cell always much longer than the median. 



First cubital and first discoidal cells distinctly separated 4 



First cubital and first discoidal cells confluent, the first abscissa of the cubitus 



absent (9"^'*^) Ncohlacus Ashmead, new genus. 



(Type, Neoblacus rnfipes Ashmead, manuscript. ) 



4. Female antennae at the most 17-jointed, in male 19-jointed; subdiscoidal nerv- 



ure forming a curve with the discoidal nervure (949) Blacita Nies. 



Female antenme more than 17-jointed, in male more than 19-jointed; subdis- 

 coidal nervure forming an obtuse angle with the discoidal nervure. 



(950) Ganychorus Haliday. 



Tribe II. ORGILINI. 

 1900. Orgiliiii, Tril)e II, Ashmead, Smith's Insects of New Jersey, p. 590. 



This tribe is based upon the genus Orgihis Haliday, which, by all 

 other recent writers, has always been placed in the subfamily Agathi- 

 dmcB, where it is clearly a disturl)ing element, its relation to these 

 insects being merely superficial. 



The genus clearl}^ belongs in this group and comes nearest to the 

 genus Evhadizon^ with which Hartig united it as early as 1837. 



The 6^7'(7^7^V^/ are distinguished from the ( <:^/yy>z;/;^/ by the straight- 

 ness of the second abscissa of the radius, which is never arcuate, as in 



I 



