OF NATURAL HISTORY. 759 



laately punctured ; segments on their middles, each with an equal 

 band which is interrupted for only a narrow space at the middle : 

 pleura with a yellow spot at the humerus : knees, tibiae and tarsi 

 yellow : venter immaculate. [377] 



Length over three-tenths of an inch. 



% Spot of the seutel interrupted or wanting ; antennae beneath, 

 dull honey -yellow; the two posterior bands of the tergum gene- 

 rally confluent in their middles ; abdomen longer and more slen- 

 der than that of the female. 



Length three-tenths of an inch. 



The sexes are more readily distinguished by the tip of their 

 abdomen than by the antennae. I have nine males and three fe- 

 males : two of the latter measure two-fifths of an inch. The 

 punctures of this species are larger and more dense than in our 

 other species. 



C. ARCUATUS. — Metathorax with numerous parallel lines; ter- 

 gum with yellow spots and bands. 



Inhabits Indiana. 



Body black, with minute, dense punctures : front with a wide 

 glabrous interval between the silvery orbits : antennae, basal joint 

 yellow, with a black line near the inner base ; sixth joint arcua- 

 ted, a little prominent inwardly at tip : hypostoma yellowish-sil- 

 very : thorax with a slightly interrupted line on the collar, of a 

 bright yellow ; a yellow transverse line beneath the seutel : wings 

 a little tinged with dusky : metathorax with numerous, small, 

 parallel lines, arcuated at base, and transversely rectilinear be- 

 hind, extending upon the pleura beneath the wings : pleura with 

 two small yellow spots before : tergum with an oblique some- 

 what arcuated, yellow spot each side of the first segment; an 

 oblique elliptic one on the second segment each side ; a reclivate, 

 transverse, lateral yellow line on the third ; remaining segments 

 each with an entire, slightly undulated, slender greenish-yellow 

 band : anal processes acute, very deeply and regularly ciliated : 

 feet yellow : coxs and trochanters black : thighs at the base 

 black ; the black portion very small on the anterior [378] pair, 

 but on the posterior pair extending on the inferior surface to 

 the tip : venter immaculate. 



Length two-fifths of an inch. 

 1837.] 



