188 STRATIOMYID^ 



known paper on British Diptera contained really excellent work, and it was most 

 unfortunate that it came to such a premature end ; Duncan founded his genus upon 

 the character of the ovate third antennal joint, but as his figure and the first species 

 of his genus refer to C. formosa that species may well be considered to be his type. 

 In 1854 Loew separated oS Microchri/sa for the small almost bare-eyed species, but 

 still retained Macquart's name of Chrysomyia for C .formosa, and very soon after (1856) 

 Eondani suggested the name of Clorisoma for the same as Loew's Microchrysa and 

 distinguished the hairy-eyed ones again as Chrysomyia, but in 1861 he proposed the 

 name of Myochrysa in substitution of the preoccupied Chrysomyia. We have there- 

 fore Chrysomyia ISIacquart and Myiochrysa Eend. as exact synonyms of Chloromyia, 

 and Clorisoma- (subsequently altered in 1861 to Chlorosia) as an exact synonym 

 of Microchrysa. Eondani's name Myiochrysa is retained in Aldrich's Catalogue of 

 North American Diptera (1905) for M. coerulea Bigot, but the original type of Bigot's 

 species seems to me to be only a small jSargus viridis. 



1. C. formosa Scopoli. Brilliant green. Face with yellowish pubescence 

 on at any rate the lower part. Tarsi altogether blackish. 



A moderate- sized handsome pubescent green fly. 



$ , Head kidney-shaped when seen from above, because the large eyes curve back 

 from the vertex and the neck is long ; when seen from in front the head is 

 about one and a half times broader than deep, and when seen in profile it is 

 very little deeper than long. Frons and face shining blue-black ; frons small 

 and bearing long and rather dense black, or grey-black, or sometimes on the 

 front part pale, pubescence • face considerably bulging, gradually widening 

 to fully one-third of the head, at the lower level of the eyes and curving round 

 to the small jowls, bearing long and rather dense pubescence which is usually 

 all pale dull yellowish or is sometimes black on the upper part (when the frons 

 is wholly black haired), and this pale pubescence extends along under the 

 eyes but hardly to the back of the head ; back of the head distinctly puffed 

 out on the lower part but practically flush with the eyes on the u.pper part, 

 bearing a short dense blackish pubescence which on the upper part forms only 

 a very short but very close ciliation ; vertex raised, black, and bearing a rather 

 long dense yellowish pubescence. Eyes large, touching for more than a third 

 of the space between the occiput and the antennae ; facets large on the upper 

 part, and though the distinction from the smaller facets on the lower part is 

 rather sudden it is not very sharply defined ; the eyes bear a long dense 

 blackish-brown pubescence all over except quite close to the upper and 

 hind margins, and in life are colored almost as in the female but with the cross- 

 band nearer the middle. Antennae (fig. 141) long; two basal joints black and 

 bearing rather conspicuous black bristly hairs ; basal joint almost cylindrical, 

 thinner but longer than the second; third joint bare, dull dark orange to 

 blackish brown, and with three distinct fairly equal annulations and one small 

 terminal one, and from the dorsal base of this small terminal one arises the 

 apparently almost apical arista ; arista about as long as the antennae, slightly 

 and shortly plumose on its thickened basal quarter, and then tapering to a 

 fine point. 



Thorax and scutellum shining blue-green, thickly and finely punctate, and 

 bearing a rather dense nearly erect dull pale brownish-yellow pubescence, or to 

 speak more correctly there is a very dense short pubescence and a sparser long 

 pubescence Avhich is about four times as long (especially noticeable on the 

 scutellum), and the result is that the shining ground colour is but little 

 obscured ; pubescence on the pleurae rather long and pale yellow, or sometimes 

 blackish on the upper part of the mesoplem-ae, Avhile very little of the middle 

 part of the mesopleurae is bare and polished though there is a space for the 

 reception of the front femora. 



Abdomen brightly shining green, nearly twice as long as the thorax but 

 broader and flatter, almost equally wide from the hind part of the second to the 

 end of the fourth segment, but the fifth segment is short and forms a flattish 

 semicii'cle, and the sixth segment is very small being only about a third as wide 

 as the base of the fifth segment. Pubescence dense, short, equal, and orange 



