^^".3.] PATTON ON THE AMERICAN STIZINI. 345 



rowed just before the tip, the disk of this narrowed portion bounded 

 laterally and posteriorly by a raised line, otherwise there is no dorsal 

 area. Seventh ventral segment of the male triangular; the dorsal 

 segment large and arched, its border rounded and very sh'ghtly sinuate, 

 the pleural pieces beneath large, subtriangular. The eighth dorsal seg- 

 ment of the male large and well formed, but concealed; the eighth 

 ventral represented (in the type) by a large and flat tridentate spine. 

 The claspers very large and complex. 



1. Megastizus brevtpennis. 



Stizus hrevipennis Walsh, Am. Ent. i, 162, $ (April, 1869). 



Larra Brcndcli Tasclienberg, Zeit. gesammten Nat. xlv, 361, $ (1875). 



To Mr. S. W. Williston we are indebted for the discovery of the female 

 of this species. In coloration it differs from the male only in having the 

 third and the last joints of the antennse mostly ferruginous and the 

 tenth and eleventh joints spotted with ferruginous beneath, and in 

 having the spots upon the scutellum of larger size. — Taken in Northwest- 

 ern Kansas, Sept. 15th. The species varies slightly. The tegulse and 

 the stripe above them vary from yellow to ferruginous, the scutellum 

 and base of postscutellum are sometimes tinged Avith ferruginous, the 

 spots upon the venter vary in size, and two spots are often present on 

 the second segment, the bands upon the third and fourth dorsal segments 

 vary in width and may be either continuous or interrupted. 



Habitat : Illinois^ Walsh and Brendel ; Kansas^ Williston and Snow; 

 Texas, Heiligbrodt. 



2. Megastizus texanus. 



Stizus texanus Cress.,Tran8. Am. Ent. Soc. iv, 222, $ 5 (1872). 



Habitat: Texas. 



Sphecienus n. g. [Spliecius, ho^). 



Syn. Spheciua A. Costa (nee. Dahlb. ). 



Type: Spliedenus nigricornis {Stizus nigricornis Duf.). 



Eighth ventral segment of the male armed with one stout spine. 

 Terminal joint of the male antennae elongate, arcuate. Basal joint of 

 the intermediate tarsi of the male excavated beneath and dilated. 

 Labrum semicircular. Submedial cell of posterior wings broad. — Xot 

 an American genus. 



Bembecintjs Costa (F. Nap., Expla. Plates, Aug. '59). 



Syn. Benil>ccinu8 and Stizomorphus A. Costa, Fanna Naples, Text (Feb. 1859). 

 Tyi)e: Bemhecinna trideus (Bembednus meridionalis Costa and StizomorphuH fridcns Costa, 

 Vespa iridens Fabr.). 



Eighth ventral segment of the male tridentate. Two of the terminal 

 joints of the male antennae armed with a spine beneath. Submedial cell 

 of the posterior wings narrow, extending no more than its own breadth 

 beyond the origin of the transverse medial ner\aire. — Not an American 

 genus. 



