57 



6. Thorax dull black, with three narrow pruinose lines, halteres yellow 



cushmani Johnson. 



Thorax dark brown, with a dorsal line and area of black, halteres brown 



vanduzeei Johnson. 



Thorax velvety black, halteres black canadensis, sp. nov. 



7. Thorax and abdomen both maculated with opalescent greenish white, 



halteres black notata Loew. 



Thorax only maculated with greenish white, halteres yellow . divergens Loew. 

 Thorax and abdomen without maculation, knobs of the halteres black 



v . talpula Loew. 



Females. 



1. Thorax and abdomen yellow 2. 



Thorax and abdomen partly black 3. 



Thorax and abdomen partly cinereous 5. 



2. Head black, antennae entirely yellow fulva Johnson. 



Head, third joint of the antennae and spots on the sides of the last two 



abdominal segments black perplexa Johnson. 



3. Abdomen broadly banded with yellow, cinereous or yellowish in front of the 



yellow scutellum, the black of. the pronotum usually vittate 



pulchella Johnson. 



Abdomen not banded'with yellow. 4. 



4. Thorax, front and abdomen marked with an opalescent greenish white, 



halteres black notata Loew. 



Thorax only marked with greenish white, halteres yellow. . .divergens Loew. 

 Thorax and abdomen entirely black, knobs of the halteres black 



talpula Loew. 



, 5. Abdomen cinereous on a yellow ground, with broad black dorsal triangles on 



the third and fourth segments, two first joints of the antennae yellow 



vanduzeei Johnson. 



Abdomen cinerous on a black ground, with black band on the third and 



fourth and a spot on the fifth segment, antennae entirely black 



obscura Johnson. 



Agathomyia brooksi, sp. nov. 



cf. — Front and face dull black, proboscis yellow, antennae black. Thorax 

 velvety black, with a large almost square yellow mark in front of the scutellum 

 extending almost to the middle of the thorax, with the anterior margin triden- 

 tate; there is also a small obscure yellow spot above the base of the wing. 

 Pleura dull black, scutellum bright yellow, with four black marginal bristles. 

 Abdomen with the first three segments yellow, the hind legs brown, the hind 

 femora and tibiae slightly enlarged with a row of fine hairs above, the metatarsi 

 about twice as long as wide. Halteres black. Wings hyaline. Length 2.5 

 mm. 



One specimen, Manomet, Massachusetts, May 31, 1919. 

 Obtained in sweeping for small insects, by Mr. Winthrop Sprague 

 Brooks. Type in the collection of the Boston Society of Natural 

 History. 



Agathomyia monticola, sp. nov. 



d\— Head and antennae black. Thorax black, shining, pleura dull black, 

 scutellum yellow, metanotum black. The first three segments of the abdomen 

 yellow, base of the first segment blackish, segments four to six black, shining. 

 Legs brown, the hind femora and tibiae but slightly enlarged, with rows of 

 bristle-like hairs above; hind metatarsi about three times as long as wide. 

 Halteres black. Wings hyaline, with a slight yellow tinge, subcostal cell 

 yellow. 



