1910] Melander — The Genus Tachidromia 47 



name of the original genus to such restricted genus or subgenus as may 

 be judged advisable, and such assignment is not subject to subsequent 

 change." Dr. Stiles ^ has given a personal ruling further that "If an 

 author, in publishing a genus with more than one valid species, fails 

 to designate or to indicate its type, any subsequent author may select 

 the type, and such designation is not subject to change." Although 

 this is a personal opinion its soundness is apparent. With these cita- 

 tions, we may take up the subsequent history of Meigen's Tachy- 

 dromia. 



Meigen's early conception of the genus was the same as our present 

 idea of the subfamily Tachydromiinae, or even the combined sub- 

 families Tachydromiinae and Hemerodromiinae, and in this he was 

 followed by the earlier writers, such as Fallen. In 1822 in the third 

 volume of the Systematische Beschreibungen Meigen separated from 

 Tachydromia the genera Hemerodromda and Drapefis. The remaining 

 Tachydromias he grouped into two divisions, A and B, with his 

 cimicoides in A. and his cursitans in B, but still retaining all in the 

 genus Tachydromia. Macquart in 1827 bestowed the name Platy- 

 palpus on division B which was the larger group, keeping the name 

 Tachydromia for the first group, but Meigen not knowing this renamed 

 the first division Tachypeza, to retain the original name for the larger 

 division. This change was published in 1830, and later he refused to 

 adopt Macquart's name because he thought his own ideas were better. 



In a paper in the Zeitschrift fuer Entomologie, published in Breslau 

 in 1863 Loew discussed the question at length and following Meigen 

 discarded the name Platypalpus because it is a poorly formed com- 

 pound of Greek and Latin. For the larger group, or those species 

 related to cursitans, he retained the name Tachydromia. The re- 

 mainder of the genus he subdivided into Tachypeza, Tachista, Dysa- 

 letria, and Phoneutisca, bestowing the name Tachista on those species 

 grouped about cimicoides. The majority of the prominent European 

 dipterists have adopted this view principally out of deference to Meigen 

 and liOew. 



The date of publication of the name Platypalpus is certain, and its 

 designation is unquestionable. We have therefore no recourse but to 

 accept it as a valid name. To this genus belongs the cursitans of 

 Meigen's original Tachydromia. Eliminating this species, the cimi- 



' Bull. 24, Hygienic Laboratory, p. 27 (1905) Rule 10. 



