SOME MUSCINAE OF NORTH AMERICA. 



GARRY DE N. HOUGH, M.D. 



GIRSCHNER divides the Muscidea into two series Calyptratae 

 and Acalyptratae. The former he divides into two families, 

 one of which is the Anthomyidae. Hypopleural bristles lack- 

 ing. If three sternopleural bristles are present, they always 

 have the arrangement i : 2 (i.e., one in front and two behind). 

 Ventral membrane usually present. Elbow of fourth longi- 

 tudinal vein (if there is any) without an appendix. 



This family Girschner divides into three groups : 



1. Coenosiinae.- -Fifth ventral segment of the male heart- 

 shaped or split in the median line from the caudal border to a 

 point beyond the middle. Fourth longitudinal vein straight. 

 Abdomen usually elongate. Sternopleural bristles present. 

 Squamulae separated from one another by an interspace that 

 is broad to the very bottom ; squamula thoracalis never broad- 

 ened towards the scutellum. 



2. Muscinae. - - Fifth ventral segment of the male with its 

 caudal border straight or moderately concave (lunulate), at any 

 rate not split beyond the middle, except in Lispe, where it is 

 three-pronged. Fourth longitudinal vein straight or more or 

 less bent up toward the third in the form of an apical cross- 

 vein. Abdomen usually short or long oval. Sternopleural 

 bristles present. Squamulae not separated from one another, 

 in contact at their attached borders ; angle between them 

 narrow and acute. 



3. GastropJdlinae. -- Sternopleural bristles absent. Fourth 

 vein straight. Costal vein reaching only to or a little beyond 

 the third vein. Squamulae but little developed, separated from 

 one another by a projecting angle. 



The Muscinae are divided into three sections : 



a. Muscinae cocnosiaeformcs. - - Front broad in both sexes. 



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