OF NATURAL HISTORY. 763 



miual band ; remaining segments with each a terminal capillary 

 baud, more or less interrupted in the middle; posterior band 

 wider and somewhat irregular : tibiaa yellow pale, [382] on the 

 inner side and tip of the exterior side black : tarsi, anterior pair 

 dull yellowish ; posterior pairs, except at base, blackish : venter 

 immaculate. 



Length over two-fifths of an inch. 



Resembles C. deserta nob., but aside from other differences it 

 may be distinguished by that species having somewhat clearer 

 wings, and the inosculation of the first recurrent nervure being 

 opposite to the middle of the second, or petiolated cubital cel- 

 lule ; the antennae also in that species are yellowish before, 

 towards the base ; the scutel has two spots in addition to the 

 yellow line behind it, and the bands of the tergum are always 

 broader than in the present species. The fallax nob. differs in 

 having the transverse yellow line on the scutel in a direct line 

 between the origin of the posterior wings ; whereas in the pre- 

 sent species it is«behind the scutel. 



2. C. SEXTA. — A broad band on each segment of the tergum ; 

 metathorax with a lateral spot. 



Inhabits Missouri. 



Body black ; head before, base of the mandibles and basal 

 joint of the antennse beneath, yellow; third joint of the antennae 

 dull honey-yellow : collar with two large yellow spots : wing- 

 scale and transverse line behind the scutel yellow; the triangular 

 impunctured space behind the transverse line very obvious, with 

 oblique lines and a longitudinal one in the middle : wings a little 

 fuliginous particularly on the margin and tip ; nervures brown ; 

 stigma yellow ; recurrent nervure of the second cubital cellule 

 entering at its middle : metathorax with a large, oval, longitudi- 

 nal, yellow, lateral spot : tergum with a broad yellow band on 

 each segment; that of the first or petiolar segment slightly in- 

 terrupted in the middle; the two ultimate ones almost ferrugin- 

 ous: feet honey-yellow, [383] more -or less vaiied with bright 

 yellow : venter with interrupted bands. 



Length over half an inch. _ 



This was given to me by Nuttall. With the exception of 

 frontata and IkUntata nob. this is the largest North American 

 1837.] 



