2o6 The Ohio Naturalist. [Vol. XIV, No. 2, 



other species of Syrphida?. The usual collection does not contain 

 very many specimens. The material for this paper was procured 

 entirely from Dury's collection, from R. C. Osborn's collection 

 and from my collection, the latter now largely with the Ohio State 

 University collection. All the known North American species 

 are represented, but none of them by more than a dozen specimens. 



Key to the North American Species. 



1. Whole body uniform shining black without yellow tomentum 



or ground color. 2. 

 Whole body not shining black often either with dense yellow 

 tomentum or yellow ground color. 3. 



2. Legs entirely black, hella. 



Middle and hind legs have the first three tarsal segments of 

 each white, nigra. 



3. Whole body uniform brown with very short yellow tomentum. 



Each side of the face below with a luteous spot, strigilata. 

 Body not uniform brown, no luteous spots on the face. 4. 



4. Thorax with yellow transverse markings, transversa. 

 Thorax without transverse markings. 5. 



5. Ground color of the abdomen marked with yellow on the sides 



of first two or three segments, varipes. 

 Ground color of the abdomen not marked with yellow, body 

 with more or less yellow tomentum. 0. 



6. Male. Tomentum of the thoracic dorsum long, entirely 



hiding the ground color, abdomen with transverse pollinose 



markings, aurinota. 

 Male. Tomentum of the thoracic dorsum short and in rows, 



not concealing the ground color, abdomen without pollinose 



markings, auricaudata. 

 Myiolepta bella Williston. One of the largest species of its genus, 

 whole body, including the legs, shining black, wings slightly 

 fumose. Length 9 millimeters. 



Female: Front and face shining black, not at all pollinose, 

 face longer than in the other species of its genus, hollowed out 

 so that nearly a uniform curve extends from the base of the 

 antenna; to the oral margin. Antenna rather short, first two 

 segments black third segment nearly round, reddish brown with 

 the upper margin darker, arista dark in color and inserted near 

 the base. Thorax with sparse hair which is partially light in 

 color, but mostly black; hair of the legs largely pale, but some 

 black intermixed in places; wings uniform pale fumose all over, 

 veins nearly black, first ]50sterior cell closed a little way from the 

 margin, the ])ctiolc much less than half as long as the anterior 

 cross-vein, second vein nearly straight at apex, thus forming a 

 distinct acute angle with the costa and differing in this respect 

 from the other North American species of its genus. Hair of 

 the abdomen pale. 



