32 THE CANADIAN ENTOMOLOGIST 



Heterachthes pallidum Hald. — Elongate, slender, cylindrical. Rather 

 dark reddish brcwn or rufc-testaceous throughout, strongly shining. Thorax 

 cylindrical, twice as long as broad, narrowed at base, finely, sparsely and ir- 

 regularly punctate without callosities or antemedian constriction as in qiiad- 

 riniacitlains. Elytra twice as long as thorax, slightly wider at base, finely 

 sparsely and irregularly punctate, each puncture bearing a very slender, erect 

 hair. Under surface smooth, glabrous. Length 6.5 mm. 



The above description, I take it, is that of the insect mentioned* as a variety 

 of IZ. gwc</nwac2</a/w5 Newm., Haldtrran's brief description following that of H. 

 qiiadrimaculatiis, being as follows: "Var. pallidum. Pale, posterior spots 

 wanting. Three lines long." As described above the differences between the 

 two forms are sufficient to restore Haldeman's name, if not as a valid species, 

 at least as a good variety. One male was taken by beating in Skinner's Hammock 

 northeast of Dunedin, March 23. The antennae, as is usual with males of the 

 genus, have joints 1 to 6 uniformly thickened, the second very small, globular; 

 the terminal joints much more slender. H. ebenus, the only other species known 

 from Florida, was taken at Moore Haven and Okeechobee City. 



(To be continued) 



THE NORTH AMERICAN DIPTERA DESCRIBED BY 



NILS S. SWEDERUS. 



BY CHARLES W. JOHNSON, BOSTON, MASS. 



In Kongl. Vetenskaps Academiens Nya Handlingar, 1787, vol. VIII, 

 pt. 4, Swederus described seven Diptera, including two from North America. 

 The author states that he has followed the classification of Linne, the genera of 

 Fabricius being placed in parenthesis. On page 287 is described Musca {Syrphus 

 Fabr.) monociilus, ''-Hab. in America Septentrionali." I am unable to identify 

 this species. On page 288, Musca {Syrphus Fabr.) americana is described, 

 "Hab. in America Sept." This is probably the species referred to as "Musca 

 tomentosa Swederus" in Osten Sacken's Catl. N. Amer. Diptera, page 136, 

 1878, in the synonymy under ' \Brachypalpus verhosits (Harris) Walker," and 

 later placed in the synonymy under Criorhina verbosa by Williston (Synopsis 

 N. Amer. Syrphida^, page 211, 1886). The name "Musca tomentosa Swederus" 

 is evidently an error, as no species by that name was described by him. In 

 regard to Musca {Syrphus) americana Swederus being the same as C. verbosa 

 Walker, there seems to be too many discrepancies, the description agreeing far 

 better with Eristalis flavipes Walker. 



The name Musca americana was previously used by Fabricius 1775. On 



the other hand, Syrphus americanus was used by Wiedemann in 1830. Does the 



use of Fabricius' genus in parenthesis by Swederus invalidate the name used 



by Wiedemann? I am inclined to think it does, as the author's intention seems 



very clear, for, following this description, three other species are described in 



which only the genus Musca is used. To avoid confusion it seems necessary to 



rename Wiedemann's species. I, therefore, propose the name Syrphus iviede- 



manni n. n., placing Mtisca {Syrphus) americana Swederus in the synonymy 



under Eristalis flavipes Walker. 



*Trans. Amer. Phil. Soc, X, 1847, 43. 

 February, 1919 



