238 long's second expedition, 



low, intermediate one small; posterior coxae eacli with a robust 

 yellow spine ; venter with transverse bands of long, dense, yel- 

 low hair. 



Length nearly two-fifths of an inch. 



9 The black color of the front extends down upon the [352] 

 middle of the hypostoma nearly to its tip; the rufous color on 

 the basal joints of the antennse is obsolete ; labrum black on the 

 disk ; mandibles black, excepting a small, rufous spot at base ; 

 the three last bands of the tergum are destitute of any rufous 

 color about them ; venter densely covered with hair : mandibles, 

 as in the male, three-toothed ; posterior coxa; unarmed. 



Length about the same as the male, but more robust. 



2. M. EMARGINATA. — Black ; a band on each abdominal seg- 

 ment, slightly interrupted in the middle, and emarginated each 

 side before. 



Lihabits Missouri. 



9 Body punctured, above glabrous; head with a small yellow 

 dot each side of the vertex ; mandil^les five-toothed ; thorax with 

 a small, whitish spot before the wings ; wiug-scale whitish, with 

 a brown spot; a whitish spot on the posterior angles, forming a 

 curve with two whitish spots on the scutel ; wings hyaline, ner- 

 vures fuscous ; feet black, a dilated whitish line on the exterior 

 side of the tibia, tarsi with dull yellowish hair ; tergum convex, a 

 whitish band on each segment, very slightly interrupted in the 

 middle, and, excepting the first one, deeply emarginated each 

 side before, the terminal segment with two rounded spots instead 

 of a band. 



Length less than seven-twentieths of an inch. 



3. M. JUGATORIA. — Black ; a band on each abdominal seg- 

 ment, interrupted in the middle and entire each side. 



Inhabits Missouri. 



9 Body punctured, above nearly glabrous; head with a yel- 

 low line on the superior part of the cheeks ; hypostoma with a 

 dilated, yellow line, which extends upon the anterior orbits 

 nearly to their -summit ; thorax with a widely interrupted line 

 before, extending round above the wings, [353] and two oblique 

 lines upon the scutel, yellow ; wings fuliginous ; feet blackish, 

 with dull rufous joints, and tarsal hair; anterior feet before dull 

 rufous ; tergum, bands yellow, not at all emarginated each side, 



