198 FORTT-FIUST HeFOET OiY THE StATE MuSEUM. 



Generic cliaracters accompanying the aboYO, wliicli will be service- 

 able iu identification, are the following (omitting the details of the 

 head-parts — antennfe, proboscis, etc.) : 



Head somewhat vertical, broad and rather short, pilose. Eyes 

 lateral, remote, oval. Ocelli three, minnte. Thorax somewhat globose. 

 SciiteUum snbtrigonate, rounded. Abdomen seven-joiuted in the 

 female, ovate-conic, tapering to the apex which is furnished with a 

 retractile tubular ovipositor. Wings incumbent, longer than the 

 body, rather broad and ovate, iridescent, ciliated, subcostal nervure 

 very short, second and third not reaching the apex, united near the 

 base, fourth passing along the center, fifth remote, the three last 

 united near the base by a transverse nervure. Halteres clavate. Legs 

 nearly of equal length, slender. Tarsi five-jointed, basal joint the 

 longest. Claws minute. 



The following brief memoranda of coloratioual features were made 

 by me from fresh examples of the fiy : 



Head and thorax ash-colored, the latter with six rows of curved 

 black bristles. Abdomen above black except at the sutures ; beneath 

 greenish, traversed by a broad black mesial stripe, which is narrowed 

 before and widens to twice its anterior width behind, interrupted at 

 the sutures. Balancers greenish, as the abdomen beneath. Legs black, 

 the tips of the femora pale. Wings iridescent, pale at base. 



Family Relations. 



The Phytomyzidce, to which this species belongs, is a small family 

 which has representation in North America in only the single genus 

 which gives it name. It finds place toward, and almost at, the end 

 of the Brachycera — the second of the three sections in which the 

 Diptera are divided, following after the more famiharly-known 

 families of Oscinidce and Agromyzidoe. 



Allied Species. 



Nothing, apparently, has been published by our writers of the 

 habits of the North American species of Phytomyza, of which there are 

 seven named in the Osten Sacken Catalogue of 1878. The European 

 species seem to be more numerous, as Prof. Westwood, in his Introduc- 

 tion to the Classification of Insects (1839) has given nineteen British 

 species, with F. latei'alis as the type; but a recent list would doubt- 

 less differ materially from this, as the result of subsequent generic 

 changes and discover}^ of additional forms. 



Of the habits of Ph. lateralis in Europe, Prof. Westwood states (loc. 

 cit., p. 573) that its larvae and pupse are found in the center of the 

 receptacles of Pyrethrum inodorum (corn-feverfew), there being seldom 

 more than one in each. Glover says that " the larva forms a gall in 

 the center of the receptacle " of the feverfew. 



