268 E. T. CRESSON, JR. 



be able to work up a very valuable monograph of this obscure, 

 but well-defined family. 



It seems that there are either many good species, or else 

 the individual variation is very great, for only a small num- 

 ber of the forms are represented by more than one or two 

 specimens ; so it is with some hesitancy that I am consider- 

 ing as new many of the forms herein described, especially 

 where only one sex is represented. 



I regret that this well marked family is in danger of los- 

 ing its old name, in fact has lost it in a recent catalogue of 

 Diptera.* The recent discovery of an early paper by Meigen, 

 published in 1800, t antedating other publications from which 

 many well known genera of Diptera date, throws a cloud 

 over Dipterological nomenclature. The absence of specified 

 generic types in that paper, together with the short generic 

 descriptions, makes it of doubtful value in the opinion of 

 some students. It was only with the help of Meigen's later 

 work, published in Illiger's Magazine in 1803, that most of 

 the genera could be placed at all, still leaving some very 

 doubtful. In looking over the situation, with the help of the 

 original literature, regarding the genus affecting this family, 

 questions arose which threw so much doubt over the whole 

 affair, that I have concluded to disregard the paper entirely. 

 I will have to go into a short analysis of the situation in 

 order to bring out these queries as they appeal to me. 



Dr. F. Hendel, who first brought this paper to the atten- 

 tion- of the scientific world, has published an extended article 

 on it, J in which he quotes the generic descriptions and gives 

 his ideas of their application. On page 59 he gives Dorilas 

 Meigen, as corresponding to the genera Microcera Meig., 

 and Pipunculus Latr., thus making these two synonyms of 

 Dorilas, which as the type genus, would change the name 

 of this family to Dorilaidae. Meigen characterizes his genus 

 Dorilas as: " Antennes a deux articulations: la seconde 



* Catalogus Dipterorum by C. Kertesz, Vol. VII, 1910. 

 t Nouvelle Classification des Mouches a Deux Ailes (Diptera L.), 

 Paris. 



% Verh. k. k. Z. B. Gesell. in Wien, LVIII, 43-69, 1908. 



