156 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.58. 



specimens from Peru that he identified as Z. dispar. He referred 

 the genus to the Drosophilidae, and redescribed and figured it. 

 Later ^ he added a few notes, attributed Wiedemann's figure to 

 Meigen. 



De Meijere ^ compared the genus with his new genus Sphyrnoceps^ 

 which he concluded is distinct because neither sex has as broad a 

 head as that of the male of ZygothHca dispar. Both Zygothrica 

 and Sphyrnoceps are referred to later by de Meijere ^, and Hendel's 

 figure is reproduced.* 



I have recently examined a large series of specimens in the United 

 States National Museum that are evidently Zygothrica dispar Wiede- 

 mann, to which species they were tentatively referred by the late Mr. 

 F. Knab. These leave no doubt that the reference to the Droso- 

 philinae is correct. Since they come from Panama, they add another 

 genus to the " North American " list. Both sexes agree in having 

 a very long proboscis, that has not been described by earlier authors. 

 It is sometimes retracted and not easily observed, which probably ac- 

 counts for this oversight. The females agree well with the descrip- 

 tion of Drosophilura caudata Hendel.^ This genus (and species) 

 was based on female specimens from Bolivia, while Hendel had seen 

 only males from Peru that he referred to Zygothrica dispar. The 

 most striking character described for Drosophilura is the long pro- 

 boscis, which Hendel had overlooked in his males. Another differ- 

 ence is that Zygothrica is stated to have two orbital bristles, 

 Drosphilura three. Just this sexual difference occurs in the series 

 of specimens that I have examined. 



There is another species in the same lot that I have here described 

 as a new species of ZygothHca. In this form both sexes have the 

 head shaped as it is in the female of Z. dispar. I can find no other 

 significant difference between the two forms, and therefore have put 

 them in the same genus. This makes it probable that Sphyrnoceps 

 de Meijere is a synonym of ZygothHca; but a more detailed descrip- 

 tion, especially of the structure of the proboscis, will be necessary 

 before this conclusion can be adopted as certain. 



We may tabulate and define the genus as follows : 



Genus ZYGOTHRICA Wiedemann. 



Zygothrica Wiedemann, 1830, Achias Dipt., Genus 16, p. 3, 

 Drosophilura Hendel, 1913, Ent. Mitth., vol. 2, p. 387. 

 ISphyrnoceps de Meijere, 1915, Tijtls. v. Ent., vol. 58, suppl., p. 58. 

 Arista plumose; two or three orbitals; vibrissae present; postver- 

 ticals large ; face prominent ; carina large ; head broader than thorax ; 



» Abhandl. k. k. zool.-bot. Ges., vol. 8, p. 219, 1914. 



"Tijds. V. Ent, vol. 58, suppl., p. 59, 1915. 



« Diptera, in Bronn's Klassen und Ordnungen 5, vol. 3, p. 45, 1916. 



* Idem, pi. 2, fig. 13. 



B Ent. Mitth., vol. 2, p. 387, 1913. 



