1915] Johnson — Noic on the Species of the Genus Acrocera 201 



small spots on the posterior margin of the third segment. A third 

 specimen, collected by Stanley W. Bromley at Southbridge, Mass., 

 June 25, 1915, represents a small male, with only a margin of yel- 

 low at the posterior angle of the fourth segment. The wings are 

 light hyaline. Length, 4 to 6 mm. 



Acrocera fascia ta Wiedemann. Figure 3. 



This is the best known species. It has been bred from Lycos 

 ocreata Hentz {L. stonei Montg.) near Philadelphia, Pa., by Dr. T. 

 H. Montgomery (Psyche, XI, 17, 1904) and by Mr. J. H. Emerton 

 from Amaurbius sylvestris at Waltham (Psyche, V. 404, 1890). 

 A specimen collected by Mr. C. A. Frost at Framingham, June 9, 

 1915, represents a small male, 3 mm. in length. The scutellum 

 is black except the apex, and the wings are a clear not a brownish 

 hj'aline. The uninterrupted bands on all of the segments readily 

 distinguish the species. The female measures 5 mm. and has the 

 scutellum entirely yellow. The wing figured shows an adventi- 

 tous cross vein between the forks of the third vein, present on the 

 left wing of one specimen, 



Acrocera nigrina Westwood. 



I am referring to this species four specimens which show some 

 variation in the abdominal markings but no more than would 

 probably exist in a large series. One has two large spots on the 

 third segment, very narrowly connected on the posterior margin. 

 The other three have small irregular spots. In all of the specimens 

 the fourth segment is largely light yellow. Legs yellow, femora 

 and tibiae obscurely brown on the middle third; squamse margined 

 with brown; wings pale brown, the second longitudinal vein want- 

 ing, a character probablj^ overlooked by Westwood. The speci- 

 mens measure from 4 to 5 mm. 



These four examples are from the following localities: Darien, 

 Conn., June 12, and Bennington, Vt., June 18, 1915 (C. W. John- 

 son); Shirley Hill, N. H., June 17, 1911 (F. W. Grigg); Quebec 

 (Provancher) Museum of Comparative Zoology. The latter has 

 the usual abdominal markings, but the second longitudinal vein 

 is indicated by a short stub at the base and by two short, inter- 

 rupted dashes on one wing and one on the other midway between 

 the base and where the apex should be. The entire absence of 



