26 AMERICAN ENTOMOLOGY. 



cies. These two spots seem to be constant as well as common to 

 both sexes. 



The plate represents two views of the natural size. 



LEPTIS. Plate XIII. 



Generic character. Antennae short, approximate, at base, tri- 

 articulate; basal joint cylindric ; second cyathifonn; third conic, 

 not annulated, and terminated by a long seta ; stemmata three, 

 situated on the vertex ; proboscis and palpi exserted, the latter 

 pilose, with its second articulation elongated ; wings divaricated ; 

 halteres naked ; onychii three ; abdomen consisting of seven seg- 

 ments. 



Obs. The species were arranged by Linne in his genus Musca. 

 Fabricius, Meigen and Latreille, in their earlier works, removed 

 them from Musca, to form a distinct group, to which they ap- 

 plied the name of Rhagio, including, as it then stood, some spe- 

 cies that have been since separated, and now stand under the 

 name of Atlierix. Those authors, in their subsequent publica- 

 tions, finding that the appellation of Rhagio presented the incon- 

 venience of a collision with that of a Coleopterous genus (Rha- 

 giurri), united in rejecting the word, and supplied its place with 

 that of Leptis, which I have adopted. 



Some of the species are common ; they are predaceous ; the 

 larvae are cylindrical, apodal, with a small horny head, and live 

 in the earth. 



Leptis ornata. — Specific character. Velvet-black; thorax 

 and abdominal bands with whitish hair ; wings hyaline ; feet 

 white. 



Leptis ornata nobis, Journ. Acad. Nat. Sciences, vol. iii. p. 34. 



Desc. Hypostoma and front with silvery white hair ; thorax, 

 particularly on its lateral margins, with silvery hair very slightly 

 tinted with yellow ; pleura, pectus and coxas black ; feet pale yel- 

 lowish ; tarsi, except at base, fuscous ; poisers pale yellow ; ter- 

 gum on the basal segment nearly covered with silvery hair ; re- 

 maining segments each with a silvery band behind, occupying 

 nearly one half of its length, and interrupted in the middle ; 

 venter immaculate. 



Obs. The specimen is a male. The species is an inhabitant 

 of Pennsylvania, and probably also of several of the neighboring 

 States. It is very closely allied to the thoracica of Fabricius. 



