AET. 10. PUP ARIA OF 100 MUSCOID FLIES GREENE. 3. 



longer than broad and its general contour follows that of the slit. 

 The ridges are heavily chitinized and are a part of the stigmal plate. 



Leaf -shaped. — Plate shaped like digitate leaf (see fig. 31). 



By the application of the characters given above, which are all of 

 a structural nature, the forms under treatment separate naturally 

 into five primary divisions or groups, some of which subsequently 

 are subdivided. The puparium of a given species may vary greatly 

 in size as well as in color. The size, of course, is variable in direct 

 proportion to the variation in the food supply, as shown by W. R. 

 Walton in a former paper.- But the shape of the puparium, regard- 

 less of its size, is quite constant, while the form of the stigmal plates 

 is remarkably constant. The latter, of course, vary in size with the 

 puparium, but their outline is practically invariable in form. The 

 location of the stigmal plates and also of the anal opening in relation 

 to the longitudinal axis of the puparium constitute a group of char- 

 acters which are not only easy of application but whose constancy 

 renders them exceedingly reliable for diagnostic purposes. The 

 author h^j found the stigmal plates of the full-grown larvae in sev- 

 eral species to be fully as reliable as in the puparia. 



The author solicits puparia of the Tachinidae and Dexiidae new 

 to the National Collection for study purposes, and will especially 

 appreciate the receipt of such puparia as can not be determined by 

 means of this synopsis. He will agree to determine such material 

 so near as may be possible and return such duplicates as are not re- 

 quired for further study. It is his intention to publish additional 

 synopses of similar character as material and opportunit}^ offer. 



EXPLANATION OF TERMS USED IN SYNOPSIS. 



Hairy type. (PI. 1, figs. 1-5.) — Surface of the puparium entirely 

 covered with short, nearly erect hairs, sometimes very short. 



Smooth type. (PI. 2, figs. 6-10.) — Puparium is practically with- 

 out hairs, excepting the usual abdominal fusiform areas. The sur- 

 face may be dull or shining. 



Pit or cavity. (PI. 2, figs. 9-10.) — A depression on the posterior 

 end of certain puparia, in which are located the stigmal plates. It 

 may be very shallow or deep. In some cases its depth is about equal 

 to the diameter or greatest width of its opening at the surface of 

 pupariimi. 



Protuberant. (PI. 10, fig. 45.) — Rising above the general surface 

 of the puparium. Viewed from the side it may be either obtusely 

 curved, conical, or truncate in form. 



Tuherculate. — A cylindrical projection, of varying length, above 

 the surface (see fig. 32) . 



» Proc. Ent. Soc. Wash., vol. 15, 1913, pp. 21-2S. 



