362 INSECTA. 



its general divisions as given by M. de Blainville in his report to the 

 Academy, Ave are unable to profit by it. Independently of this, we 

 should have been compelled to pass beyond our prescribed limits, and 

 perhaps have terrified the young naturalist, by an exposition of the 

 multitude of new genera he has established in this tribe, several of 

 which, even in the opinion of the reporter, appear to differ but little 

 from each other. We even think that the work of M. Meigen, with 

 the exception of the revision of the two genera above mentioned, is 

 amply sufficient for the actual wants of the science. 



Dr. Desvoidy has employed but very few characters of his own in 

 designating these groups. There are even some which he might 

 have used to advantage, such as the disposition of the nervures of the 

 wings, which he has neglected, at least in the work presented to the 

 Academy. His first family, that of the Calypterees, is identical with 

 the one I call Creophiles in my " Families Naturelles du Regno 

 Animal," and which, besides, was already established in my preceding 

 works. According to the analysis of his Memoir given by M. de 

 Blainville, it is evident that the characters of the nine other families 

 of the Myodaires are generally founded on the mere diversity of 

 their mode of habitation, their colours, and on some other vague 

 considerations. 



We will endeavour to arrange the genera of Messrs. Wiedemann 

 and Fallen which Ave have been able to study, in our former method, 

 but with some modifications Avliich the observations of these cele- 

 brated naturalists, and others of my own, render necessary. 



This tribe will comprise the genus 



Muse A, Lin. 



Antennae inserted near the front, palpi placed on the proboscis, and 

 retiring with it into the oral cavity, and tranverse nervures in the 

 Avings, characterize a first section of the winged Muscides, which will 

 include eight principal groups or sub-tribes. 



Those of our first division, Creophil;e, have large alulae, which 

 almost completely cover the halteres. The wings are almost always 

 distant, Avith the two terminal and exterior cells of the posterior edge * 

 closed by a transverse nervure. 



Of the species Avhich alvA^ays present these characters, we AA'ill dis- 



* The most external one is situated under a narrow, elongated cell, closed by the 

 posterior margin, which may be considered as a sort of cubital cell. In the follow- 

 ing divisions, this exterior cell is not closed by a transverse nervure. The second, or 

 that which adjoins the inner side of the preceding one, is also closed in the last of 

 the Muscides; but it is no longer terminal, and frequently it is even shorter; the 

 longitudinal nervures whicli form the sides are prolonged to the posterior margin, 

 thereby forming another cell, which becomes terminal and incomplete. In the Creo- 

 philee the two nervures are not (or but very slightly) prolonged beyond the closed 

 cell. 



