Vol. 5, p. 69-72. November 14, 1923. 



Occasional Papers 



OF THE 



Boston Society of Natural History. 



NEW AND INTERESTING SPECIES OF DIPTERA. 

 BY CHARLES W. JOHNSON. 



This paper adds two interesting genera to the New England 

 fauna: Spania and Hilarimorpha, belonging to tHe family Rhagio- 

 nidae (Leptidae). A new species of Allognosta of the family 

 Stratiomyiidae is also described, with a note on Allognosta similis 

 Loew. 



Spania nigra Meigen. 

 Spania nigra Meig., Syst. Beschr., vol. 6, p. 335, tab. 66, f. 12-14, 1830. 



Among the material collected at Witch Hole Pond, near Bar 

 Harbor, Maine, June 21, 1921, was a single male specimen of what 

 is evidently this interesting little species. It agrees with the 

 description, except for a discrepancy in the venation. The 

 venation, however, is exceedingly variable in European specimens, 

 and this inconstancy is described by Verrall (British Flies, vol. 5, 

 p. 318, 1909) as follows : " The two upper veinlets from the discal 

 cell usually sessile, but frequently separated (sometimes widely) 

 and not uncommonly petiolate as in Ptiolina, while the third vein- 

 let is usually abbreviated, but is sometimes complete; it is also 

 not uncommon to find a spurious cross-vein connecting the two 

 upper veinlets from the discal cell soon after their origin and 



Fig. 1. — Spania nigra Meigen. Typical venation, after Meigen. 

 Fig. 2. — Venation in a specimen from near Bar Harbor, Maine. 



thereby forming a small complete cell above the end portion of the 

 discal cell, discal cross-vein hardly before the middle of the discal 

 cell; anal cell sometimes barely closed or sometimes distinctly 

 petiolate ; it is very usual to find the venation varying differently 

 in the two wings." In the specimen before me the anterior or 



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