INSECTA BRITANNICA. 



DIPTERA. 



BBACHYCERA. (See Vol. I. p. 8.) 

 FAMILY XXVII. MUSCID^. 



p., Latr. G. C. (1809) ; Lam. ; St. ; Curt. ; Westvv. Musca 

 p., L. Muscides p. et Stomoxydes, Fal. ; Meig. Sarcostomae p., 

 Dumr. Chetoloxae p., Dumr. Myodaria p., Dumr. DicJiaeia, AtJieri- 

 cera p., Mcq. ; Zett. Muscida et Stomoxydce, Lea. Muscides, Mcq. 

 Muscidii, Bigot. 



Caput sat magnum. Oculi subtus genis inclusi. Proboscis distincta. 



Antennarum articuli apicales aristam fingentes, articuli tertii dorso 



insertam. Alas confertas, rarissime abortive ; vena cubitalis simplex ; 



vena spuria apud venas brachiales nulla ; lobus axillaris rotundatus. 



Head large ; proboscis distinct ; eyes below bounded by the cheeks ; 



last joints of antennas forming a slender arista, attached to the third 



joint on its upper edge. Wings perfect, very rarely abortive ; cubital 



vein simple; brachial veins without spurious vein; axillary lobe 



rounded. Halteres of some hidden, of others uncovered. 



The Muscida are the most remarkable of the families of Diptera, 

 on account of their very numerous groups, species, and individuals, 

 of their extensive variation of structure, and of their great import- 

 ance in the economy of nature. The nomenclature of some parts 

 of their structure requires a short explanation. Thefrons extends 

 from the hind part of the head to the base of the antennae, and 

 occupies the space between the eyes ; its hinder part is the vertex, 

 before which are the ocelli; its fore part contains Hit frontalia, 

 which are dark -coloured, and more or less linear ; in some cases 



VOL. II. B 



