NEW SPECIES OF COLORADO SYRPHIDiE. 



Charles R. Jones. 



Microdon similis n. sp. 



Length 14 mm. Head black, clothed with yellowish pile, front wide, 

 sides nearly parallel throughout, a narrow, shining oblique transverse 

 groove running from the base of the antennae to the eyes; antennae 

 dark fuscus, the first joint linear, equal or sub-equal in length to the 

 second and third together, arista black, tip slighth^ reddish. Thorax 

 of a bronze black, clothed with yellow pile. Scutellum rounded, black, 

 with the apex slightly emarginate, but plain, pile of the same color as the 

 thorax, slightly longer and more abundant. Abdomen black, short, 

 slightly shining, less than twice as long as wide, finely punctulate; dorsum 

 with stout black pile, the lateral margins with yellowish pilose, pile of the 

 first segment long, whitish, and forms a distinct uninterrupted trans- 

 verse cross-band on the posterior portion of the segment. Legs black, 

 pile of the tibia whitish, hind metatarsi slightly diolated and not quite 

 as long as the remaining joints together, clothed with short, stout, 

 reddish pile. Wings sub-hyaline, the veins narrowly blackish. 



Two specimens, Poudre Canon, Colorado., C. S. Mead, Coll. 



M. similis differs from M. tristis in that the thorax of the 

 latter is obsolete cupreous lineate and the former is not; that 

 the antennae of tristis is testaceous at the base while the 

 antenna of similis is entirely black; that the length of tristis 

 is from 7 to 10 mm., while similis is 14 mm.; and in that the 

 emarginated scutellum of tristis is armed with a sharp, tooth- 

 like projection on each side and similis is only slightly emargi- 

 nate and plain. 



Melanostoma cherokeenensis n. sp. 



Length, cf , 7 mm., 9 , 7.5 mm. General color black, body linear, 

 face bluish, yellow reflecting, white pollinose, pile black and white, 

 tubercle rounded, not very prominent, shining black. Front of female 

 slightly depressed, with whitish pollinose and black pile; vertex shining 

 black, black pile, cheeks bluish black, white pollen and black pile near 

 the eye, white pile along border. Occiput broad, whitish pollen and 

 pile. Antennae brownish black, third joint rounded. Thorax shining 

 metallic green, with black and white pile. ' Pleura with white pollen 

 and pile. vScutellum yellowish, lightly dusted with light pollen, which 

 gives it a bluish reflection, dorsum with long black, sparse pile, bordered 

 with whitish pile. Abdomen velvety, bluish-black with short, white 

 pile and three interrupted yellow cross-bands, all separated from the 

 lateral margin. In the female, the spots of the second segment are 

 orange, quadrate, and near the middle of the segment; the lateral portion 

 lightly dusted with white pollen ; spots of the third and fourth segments 



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