C. W. Johnson.
Notes on the Species of the Genus Dioctria.
Psyche 25:102-103, 1918.

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102 Psyche [October
NOTES ON THE SPECIES OF THE GENUS DIOCTRIA. BY CHARLES W. JOHNSON,
Boston Society of Natural History.
On a window of the Boston Society of Natural History, I ob- tained, June 28, 1916, a specimen of Dioctria, but being unable to identify it at the time it was set aside to await more material. On
July 6, 1917, while walking along Rawson Road, Aspinwall Hill, Brookline, Mass., I caught'four specimens of the same species- two males and two females. After a careful study and comparison with specimens in my collection from Lyndhurst, New Forest, England (8 9 ) determined by E. E. Austin, I can only refer it to Dwctria baumhaueri Meigen. Wishing to see if the species was still to be found, I visited the place again this year (July 4) and captured five males and four females.
The sudden appearance and apparently restricted distribution of a spec'es after so many years of careful collecting in the vicinity of Boston, would indicate a comparatively recent introduction, possibly on the root of some plants, many of which have in the past been 'mported. 'The species can be distinguished by the following diagnosis.
Dioctria baumhaueri Meigen.
Face black with silvery white tomentum, mystax white, front and vertex black, shining, antennae black, third joint about as long as the first and second together. Thorax with a sparse yellow tomentum having two narrow lines of black, a transverse band of white tomentum on the pleura extends to the front coxse, also with irregular patches above the middle and posterior coxse, all the cox* with long white hairs below. Abdomen black, shining. Front and midd:e legs yellow, a line on the upper side of the femora, tips of the tibise and tarsi black, posterior legs black, a spot on the under side of the femora at the base, and the base and tip of tibiz. yellow. Halteres light yellow, wings hyaline. Length, 9-10 mm. In PSYCHE, vol. 24, p. 117, 1917, Mr. Nathan Banks described several new species, some of which were formerly confused with Dioctria albius Walker, but readily separated by the male genitalia. In going over my collect'on in connection with this paper, I have



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19181 Johnson-Notes on the Species of the Genus Dioctria 103 noted a more extended distribution of some of the species and also the fact that two of the names used are preoccupied. In calling Mr. Banks' attention to this he said that he did not have access to the catalogues at the time and desired me to correct these in con- nection with my notes.
Dioctria brevis Banks.
This species has been taken by the writer at Mt. Tom, Mass., July 14, 1905; Delaware Water Gap, N. J., July 11, 1898b and Aquia Creek, Va., May 24, 1896.
Dioctria banksi nom. nov.
D. longicornis Banks, PSYCHE, xxiv, 118, 1917, not Meigen, 1820. Four specimens of this species were collected near Long Branch, N. J., June 9, 1913. A specimen from Philadelphia, Pa., (June 22, 1893), is also in my collection. Dioctria sackeni Williston.
A specimen of what is undoubtedly the female of this species was taken by the writer near Ricketts, North Mt., Pa., June 9, 1898, at the same time and place that a male was also captured. It has the bright yellow tomentum of the face, front and thorax, and the yellow legs of the male, but the wings are uniformly hyaline with a slight yellowish tinge near the base.
Dioctria media Banks.'
A single specimen of this species from Seattle, Wash., collected years ago by the late Professor 0. B. Johnson is in my collection. Dioctria henshawi nom. nov.
D. fluuipes Banks, PSYCHE, xxiv, 119, 1917, not Meigen, 1804. The name flavipes being preoccupied in this genus, the species is dedicated to Mr. Samuel Henshaw who collected the type at Yakima, Wash., July 2, 1882.




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