NATURAL SCIENCES OF PHILADELPHIA. 105 



New Species of MORDELLISTENA collected in Illinois. 



BY CHAS. A. HELMUTH, M. D. 



A. Hind tibiae with two oblique, parallel, equal ridges. 



a. First joint of hind-tarsi with two, second with one ridge. 

 M. nigricollis. Body black, head rufous, thorax entirely black ; anterior 

 feet and middle tibia? and tarsi testaceous ; posterior feet and abdomen tinged 

 with testaceous ; elytra with two yellow bands, the anterior one interrupted at 

 the suture ; -08. (an Var. M. trifasciatce ?) 



M. dimidiata. Fuscous, linear; head, thorax, antenna?, anus, anterior and 

 middle feet, and posterior tibia? and tarsi reddish-yellow, ridges black ; elytra 

 fuscous, with light-brown pubescence, suture and lateral margin very narrowly 

 piceous ; -09. 



M. biplagiata. Black ; elytra with a reddish-yellow oval humeral spot ; 

 basal joints of antennae, palpi, tibia?, tarsi and abdomen reddish, ridges black; 

 13. 



6. First and second joints of hind-tarsi each with two ridges. 

 M. bipdstulata. Black, mouth, front, two small spots on the apical margin 

 of the thorax and anterior feet reddish-yellow ; pubescence light-brown seri- 

 ceous ; "09. 



c. First joint of hind-tarsi with three, second with two ridges. 

 M. eubkilabeis. Black ; linear ; mouth rufous, -13. 



B. Hind tibia? with two parallel ridges, the anterior one extending almost 



across the outer face of the tibia?. 



a. First joint of hind-tarsi with two, second with one ridge. 



M. picilabris. Black ; pubescence grayish ; mouth and basal joints of an- 

 tenna? piceous, -08. 



b. First joint of hind tarsi with three, second with two ridges. 



M. guttulata. Black ; mouth piceous ; elytra with numerous spots of cine- 

 reous pubescence ; *11. 



C. Hind tibiae with three short, oblique, parallel ridges, and a rudiment of a 



fourth one. 

 a. First joint of hind tarsi with three, second with two ridges. 



M. scalaris. Black ; mouth, anterior feet, and four basal joints of antenna? 

 piceous ; pubesceuce grayish-brown ; thorax with three black clouds, each 

 elytron with a very undulated band before the middle, beginning near the 

 lateral margin and joining that of the other side at the scutellum, and a large 

 oblong spot near the apex fuscous ; '17. 



D. Hind tibia? with four ridges. 



a. First joint of hind tarsi with four, second and third each with three 

 ridges. 



M. fusco-atra. Very slender ; dark fuscous ; four basal joints of antenna?, 

 anterior and middle feet piceous ; pubescence brown-sericeous ; "14. 



b. First joint of hind tarsi with five, second with three ridges. 



M. suturella. Black ; pubescence of head and thorax brownish, of elytra 

 black, with the suture narrowly gray ; -17. 



c. First joint of hind tarsi with five, second with three, third with two 

 ridges. 



M. rofiventris. Black ; pubescence of head and thorax brownish, of elytra 

 black, with the suture narrowly gray ; abdomen rufous, varied with black ; 

 20. 



1864.] 



