1915] Johnson — Note on the Species of the Genus Acrocera 199 



Table of Species. 



Dorsum of the thorax marked with yellow 2 



Dorsmu of the thorax entirely black 3 



2. Thorax with two elongated spots or stripes (Wash.) liturata Will. 



Thorax with two cuneiform markings (N. Y., N. H.) subfasciata Westw. 



3. Venation typical (N. Y., Mass., Me.) bulla Westw. 



Venation not typical 4* 



4. Second longitudinal vein wanting 5 



Second longitudinal vein rudimentary, present only at the apex (D. C, 



Pa., Que., Mass.) bimaculata Loew 



5. Third longitudinal vein branched and the anterior cross vein present 6 



Third longitudinal vein with the branch and the anterior cross vein obso- 

 lete or wanting 7 



6. Abdomen with a complete uninterrupted fascia on all the segments (Ga., 



Pa., 111., Mass.) fasciata Wied. 



Abdomen with irregular maculation on the third and fourth segments (Ga., 



Conn., Vt., N. H.) nigrina Westw. 



Abdomen yellow, except at the very base; veins extremely light (Wis., Me.) 



obsoleta V. d. Wulp 



7. Abdomen black, wings fuscous at the base (Ga.) fumipennis Westw. 



Abdomen yellow, base of the segments black; wings hyaline (Ga., Md., Pa., 



Wis.) iinguictilata Westw. 



Acrocera subfasciata Westwood. Figure 1. 



A specimen collected by J. C. Bridwell at Pelliam, N. H., Sep- 

 tember 8, 1905, agrees well with Westwood's description, except 

 that the yellow cuneiform markings on each side of the anterior 

 part of the thorax extend in two very narrow subdorsal lines to the 

 base of the scutellum, a likely variation, apparently resembhng A. 

 liturata Will., which may prove to be an extreme variation. The 

 abdomen is mellow with dorsal and lateral spots of black, those on 

 the second segment narrowly connected with those on the sides. 

 Venation typical. As Westwood lays considerable stress on oliso- 

 lete veins and Williston does not mention the venation oi A.liiurata, 

 I take it for granted that both are typical in this respect. 



Acrocera bulla Westwood. 



Again I take it for granted that Westwood's species has typical 

 venation. A specimen collected at Bailey's Island, Me., August 

 20, 1915, by Dr. G. M. Allen agrees well with the description. 

 The specimen referred to has very light yellow markings, those 

 on the second segment consisting of two widely separated 

 triangular spots on the posterior margin; the third segment 



