06 THE CANADIAN ENTOMOLOGIST. 



A careful study of this material seems to make it clear that M. Boscii, 

 Macq., and M. parvula, Loew, are one and the same species. Absolutely 

 the only differences in the descriptions of these two species are in the 

 markings of the abdomen, and they are notoriously variable in the species 

 of this genus. In Boscii the first segment is black and the anterior half 

 of the second is yellow; in parvula the anterior margin of the first 

 segment is yellow and the anterior margin of the second is black. Now, 

 one of these specimens shows a very narrow yellow anterior margin on 

 the first segment, and the other specimen has it entirely black, but in both 

 the second segment is black on the anterior margin. Such a combination 

 of the only characters that separate these species in individual specimens 

 seems to make their identity certain. 



Mesogramtna marginata^ Say. 



One specimen from Orizabo,- Mexico ; Jan. This species has been 

 recorded from all parts of the United States and from several points in 

 Mexico. 



Bacclia Tarclietius, Walker. 



There has been recorded only one specimen of this species besides 

 the type in the British Museum ; this one was from New Jersey [Mr. Keen] 

 and is now in the National Museum. In the collection of the University 

 are two specimens — one from Philadelphia, Penn., and the other from 

 Mobile, Ala. — both taken by Mr. C. W. Johnson, and from his collection. 

 They are both females and differ from the description of the male in 

 having two yellow spots similar to those on the third segment on the fifth. 

 In all other respects the description applies exactly. 



Baccha clavata, Fabr. 



This species is a common one in the Southern States. It has been 

 recorded from Georgia, Florida, Arizona, and two localities in New 

 Mexico; Schiner mentions it " aus Sud- America." The capture of a 

 specimen at Lincoln is therefore quite remarkable and gives the species a 

 very much enlarged range. This specimen, a male, was taken near the 

 flowers of a species of aster growing near the water, in September, by the 

 writer. The larva of this species is a very beneficial one in districts 

 where oranges are grown, as it feeds on the aphids that often infest the 

 trees. 



