OP NATURAL HISTORY. 743 



obscure yellow, longitudinal spot each side at tip : tergum with a 

 perlaceous iridescence : on each segment a slender yellow [301] 

 band on the posterior submargin, a little undulated obtusely on 

 its anterior edge, not abruptly emarginated on each side ; on the 

 anterior submargin of the segments an impressed transverse line : 

 pleura, a small yellow spot beneath each wing ; wings hyaline, a 

 slightly dusky mai-gin at tip : feet, coxae with a yellow spot : tarsi, 

 excepting their tips : thighs at tip or a Une above, and anterior 

 pairs of tibiae yellow : venter five spotted each side. 



Length from three-fifths to seven-tenths of an inch. 



This is so much like M. suhulata nob., that it is not without 

 much hesitation that I give it as distinct. It is, however, 

 much larger and more robust, and the form of the bands 

 of the tergum is different ; those of the subulata being abruptly 

 notched each side of the middle as in the i-alvulus Fabr., whereas 

 in the bands of the present species, instead of the abrupt notch, 

 is an obtuse and dilated undulation of the edge. 



A variety occurs in Missouri, of which the wings are yellow- 

 ish, and the second recurrent nervure is confluent with the divi- 

 ding nervure of the second and third cubital cellule. 



2. M. suBUL.\TUSnob. *S'«^y^rt, Western Quarterly Reporter. — 

 A variety inhabits Mexico in which the abdominal bands are less 

 abruptly emarginate each side. 



SAPYGA Latr. 



S. CENTRATA.— Black, with yellow spots; abdomen 5-banded. 



Inhabits United States. 



Body black : head • : thorax with a transverse spot 



each side before, two on the middle, one beneath the superior 

 wing, and two large ones behind, yellow : [302] wing hyaline ; 

 nervures fuscous : stigma brown : radial cellule fuliginous: ter- 

 gum, each segment, excepting the first, with a yellow, dilated 

 band on its middle and more or less interrupted : venter with a 

 transverse spot each side on the third, fourth and fifth segments : 

 feet yellow : thighs, except at the tip, black : tarsi honey-yellow. 



Length about three-tenths of an inch. 



Var.?<*. Spots ferruginous. 



Length nearly two-fifths of an inch. 

 1835.] 



