TEXAN HYMENOPTERA. 233 



ginous; scutellum ferruginous, black posteriorly ; postscutellum yellow ; mob- 

 thorax yellow-ferruginous, black on basal middle and down the deeply chan- 

 nelled middle to the apex; pleura ferruginous, with anterior and posterior 

 margins black, in one specimen entirely black, with ferruginous spot beneath 

 tegulae; wings fusco-hyaline, paler at apex and on posterior margin, costa yel- 

 low, blackish in marginal cell ; legs yellow-ferruginous, tibise and tarsi yellow ; 

 abdomen shaped much like that of Belfragei. but stouter, the second segment 

 more convex, almost globose; first segment smooth, polished, with dense short 

 erect yellowish pubescence, ferruginous, base and disk of apical half black, 

 narrow apical margin yellow; second segment shining, with sparse fine punc- 

 tures and short dense yellowish pubescence, yellow with a large blackish an- 

 gular band, sometimes quite broad, starting from the basal middle and forking 

 posteriorly at about the basal third, reaching the lateral margin at the apex, 

 from whence it narrowly margins the segment to the base, a shallow depres- 

 sion near the apical middle, apical margin narrow, deeply impressed and dull 

 ferruginous; remaining segments ferruginous, tinged with yellowish above: 

 venter ferruginous, more or less tinged with yellowish. Length .55 inch. 



%. — Smaller, less robust; clypeus narrower, and silvery-sericeous; apical 

 joint of antennae slender and acute; angular band on second abdominal seg- 

 ment ferruginous, remaining segments black, banded with yellow. Length 

 .48 inch. 



Three % 9 specimens. (Belfrage.) A very handsome and dis- 

 tinct species. 



Monobia quadridens. 



Vespa quadridens, Linn. Syst. Nat. ii., p. 951. 



Seven % 9 specimens. (Belfrage; Boll; Heiligbrodt.) 



Rhygchium dorsale. 



Vespa dorsalis, Fabr. Ent. Syst. ii., p. 265. 



Bygchium balteatum, Say, Bost. Journ. Nat. Hist, i., p. 383. 



Rygchium louisianum, Sauss. Mon. des Guepes Sol. p. 106, pi. 13, fig. 9. 



Twenty-two % 9 specimens. (Belfrage; Boll; Heiligbrodt.) This 

 fine species is exceedingly variable both in size and color, being some- 

 times almost entirely black, and sometimes entirely ferruginous, ex- 

 cept the yellow band on first abdominal segment which is always con- 

 spicuous. 



Odynerus tigris. 



Odynerus tigris, Sauss. Rev. Mag. Zool. 1S57, p. 273. 



Five % 9 specimens. (Belfrage; Boll.) 



Odynerus quadrisectus. 



Odynerus quadrisectus, Say, Bost. Journ. Nat. Hist, i., p. 385. 

 Odynerus Bellone, St. Farg. Hym. ii., p. 660. 



Two 9 specimens. (Boll.) 



TRANS. AMER. ENT. SOC. IV. (30) NOVEMBER, 1872. 



