CHRYSOTIMUS. 221 



forward, parallel to the third vein and ending into, or somewhat 

 beyond, the tip of the wing. Hypopygium small and imbedded. 



The species of Ghrysotimus were formerly united with the 

 species of Chrysotus. The principal difference between these 

 genera consists in the structure of the thoracic dorsum. Chry- 

 sotus has immediately before the scutellum a small, more or less 

 distinct, transverse swelling, which is separated from the rest of 

 the surface by a rounded impression, and the convexity of the 

 thorax begins here. In Chrysotimus this transverse swelling is 

 entirely wanting, and the thorax shows in the middle of its hind- 

 most part a rather conspicuous, distinctly concave surface, slop- 

 ing towards its posterior margin. Moreover in Chrysotimus the 

 feet are much less hairy, the wings comparatively a little larger, 

 the appendages of the hypopygium more concealed, the integu- 

 ments of the whole body softer, the bristles upon thorax and scu- 

 tellum not black, but yellow, and the abdomen always, at least 

 partially, of a yellow color, which is not the case with any of the 

 genuine species of Chrysotus. 



The name of the genus (from zprcroj gold, and n^*?, honor) re- 

 minds us of the coloring of the species, as well as of their former 

 connection with the genus Chrysotus. 



Besides the two North American species, described below, only 

 European species are known. 



1. C pusio Loew. J . — Laete viridis, abdominis flavi segmento ultimo 

 viridi, antennis palpisque nigris. 



Bright green ; abdomen yellow, the last segment green ; antennae and 

 palpi black. Lorjg. corp. 0.07. Loug. al. 0.09. 



Syjt. Chrysotimus pusio Loew, Neue Beitr. VIII, 74, 1. 



Face dark-green with a thin white-grayish dust. Palpi brown- 

 ish-black, appearing rather pale on account of a white-grayish 

 dust. Antennae entirely black ; front shining metallic-green ; the 

 frontal bristles black, in another direction fallow-brownish, with 

 a yellow lustre. The cilia of the whole orbit yellowish. Thorax 

 and scutellum pale metallic-green, with whitish dust, but shining 

 and fringed with yellow bristles. Metathorax and pleurae of the 

 same pale-green color, the latter with thick whitish dust. Abdo- 

 men uniformly yellow, only on the upper side of the last segment 

 green. All the coxae and feet yellow, only the last joint of the 



