NORTH AMERICAN DIPTERA. 279 



THE IWOKTII AMKRICAM GE9fEKA OF CALYPTRATE 

 l»irSC'ID.15. Paper IV.» 



SARCOPHAGID-S] and MUSCID-S3 s. str. 



BY C. H. TYLER TOWNSEND. 



This paper furnishes a synopsis of the North American genera of 

 Sarcophagida.', including, as heretofore in this series of papers, the 

 West Indian fauna. Following this is a synopsis of the North 

 American genera of Muscidse s. str. In the preceding paper of this 

 series, 43 Dexiid genera are tabulated ; and in the present paper there 

 are 8 Sarcophagid, and 17 Muscid (.s. sir.) genera included in the 

 tables. Three genera, which are preceded in the tables by a circle, 

 have not yet been found in North America. Following the tables 

 will be found notes on certain genera which claim attention. 



One more paper, which will attempt a synojjsis of the Anthomyiid 

 genera, will conclude this series of papers on the North American 

 Calyptrate Muscidse. 



Synopsis of the North American genera of 

 SARCOPHAGIDiE. 



1. Tibise beset on the outside with a comb -like row of strong, regularly ar- 



ranged bristles Theria R. D. 



Tibi£e at most with weak bristly hairs, or with scattered stronger bristles 

 not regularly arranged in a row 2. 



2. Hind and middle tibise and femora thickly beset with bristly hairs in the % , 



the hind tibiaj somewhat arcuated Plirissopoda Mcq. 



Tibiie and femora not beset with such hairs in either sex 3. 



'A. Apical cell open 4. 



Apical cell closed in the margin : front of % wide; arista long plumose. 



Marcopliilodcs B. B. 



4. Front in both sexes very broad, and of nearly the same breadth ; arista usually 



short plumose o Sarcopliila Edi. 



Front of % always much narrower than that of ? : arista usually long 

 plumose ^• 



5. Sides of face with a distinct row of small bristles on lower portion near eye 



margin ; facial ridges with not more than two or three short bristles 



above vibrissse; gray colored species 6. 



Sides of face bare below; facial ridges bristly nearly half way up; species 

 with metallic green or blue reflections 7. 



* Paper I was published in the Prnc. Ent. Soc. Washington, ii. pp. 89-100. 

 Paper II, in Trans. Am. Ent. Soc. xix, pp. 133-144. Paper III, in Trans. Am. 

 Ent. Soc. xix, pp. 273-278. 



TRANS. AM. ENT. SOC. XIX. DECEMBER, 1892. 



