1919] Johnson — Variation of Tahanus atralus Fahricius 163 



yellowish, the other veins hardly discernible; apical branch of the 

 subcosta lacking; radial area open also at the distal end. Length: 

 3.0-3.5 mm. 



Range. South Africa: Salisbury, 5050 ft. (F. L. Snow coll.). 



Types. 1 female and 1 male cotj'pe in the collection of the 

 Kansas State Museum; and 1 male cotype in the author's collection. 



One of the male specimens is marked as collected in June, 1900; 

 the other male and the female in Dec. 1900. In Das Tierreich, in 

 Dalla Torre and Kieflfer's key the species would run down to A. 

 coriacea from which it is distinct in having all parts of the thorax 

 black and the legs uniformly rufous-brown. The genus has not 

 heretofore been known from Africa south of the north coast. 



ON THE VARIATION OF TAB AN US AT RAT US 

 FABRICIUS. 



By Charles W. Johnson, 

 Boston Society of Natural History. 



This species, in its distribution along the Atlantic coast from 

 Maine to Florida, is subject to considerable variation, which fact 

 was referred to by Osten Sacken in his Prodrome (Memoirs Boston 

 Soc. Nat. Hist., vol. II). On page 455 he says: "Northern speci- 

 mens, for instance those found around Boston, often have the wings 

 pale brown, even yellowish brown toward the posterior margin." 

 Professor Hine in describing this form as T. nantuckensis from Nan- 

 tucket, seems to have overlooked this reference, for he says: 

 "There is reason to believe that this insect has become isolated on 

 the Island for it has not been taken elsewhere so far as I can find." 



Tabanus atratus var. nantuckensis Hine 



Tahanus nantuckensis Hine, Ohio Jour. Sci., p. 271, 1917. 



At most this is only a variety of T. atratus, apparently confined 

 to the New England coast. Its "smaller size" does not count, for 

 I have typical T. atratus as small as nantuckensis (20 mm.). This 

 leaves for consideration only the color of the wings — dark brown 

 with the posterior half or more, yellowish brown, as a distinguishing 

 character, which in a large series from along the coast merges into 



