E. T. CRESSON, JR. 59' 



Chaetomacera unicolor Loew 



1S47. Tctanoccra luiieolor Loew, Stett. Ent. Zeit., viii, 199. 



In color and structure similar to clara Loew, but the wings are 

 immaculate, with only the cross-veins clouded. Frons rather 

 shining, with the abbreviated stripes polished and not well de-' 

 fined. Second antennal joint nearly as long as third, and as 

 long as broad; third joint conical but rounded. Length, 5 mm. 



Originally described from Europe. I have compared my 

 material with European specimens. 



I have two males belonging here from Fort Kent, Maine, 

 August 17, (C. W. Johnson), [B. S. N. H.]. 

 Chaetomacera elata Fabricius 

 1781. Musca data Fabricius Spec. Ins., ii, 441. 

 1820. Tetanoccrn data Fallen, Dipt. Suec, Sciomyz., 9. 



This species as here considered, is probably a composite, but 

 will give some trouble if any attempt is made to separate it into 

 all of the apparent components. However, there are several 

 forms represented by a few typical specimens, in the material at 

 hand, which it may be worth while noting, and which are con- 

 sidered, at present, as varieties. 



The characters, apparently of most value or stability, for tliis 

 species sensu latiore, are the larger size (6 to 8 mm.) ; broad, quad- 

 rate or rectangular second antennal joint; opaque apical margin 

 of frons; long plumose arista; more or less vittate mesonotum, 

 and immaculate wings. In regard to the second antennal joint, 

 most of the varieties are readily distinguished from their closest 

 ally, unicolor, but elata, typically, is not so easily defined except 

 in its larger size. Hendel,^" in his description oi elata, mentions 

 the abdomen having a more or less distinct median stripe. I 

 have not seen any indication of such stripe in our material or 

 in the specimens of European specimens examined. This phase 

 suggests a question as to the possibility of there being two species 

 confused under elata in Europe. Our vicina has the abdomen 

 vittate, but I hardly think it would prove to be conspecific with 

 the true elata. If the type of elata could be examined we would 

 be able to satisfy these queries. 



The following description is based on specimens from Europe, 

 determined as elata, which I can only take as being correctly 



1° Verb. K. K. Zool.-Bot. Gesell. Wien, 1, 342, 1900. 



TRANS. AM. EXT. SOC, XLVI. 



