32 STRUCTUEE OF CERTAIN DIPTEROUS LARV.E. 



scabrous flattened elevation bearing two approximate smooth 

 tubercles. The tip has a faint conelike process each side below the 

 stigmata; the latter are slightly elevated, each showing three straight 

 slits, wide apart and directed toward those of the opposite plate. 



Dacus curcurhitse Coq. 

 (Plate V, figs. 101, 102, 104.) 



Head bilobed from above, each lobe bearing a distinct antenna; 

 mandibles two, distant; anterior ^piracies long, with about 20 lobes. 

 Ventral segments 6 to 12 with swollen spinulose areas. The last seg- 

 ment shows below a transversely elliptical spinulose area, rather 

 depressed, and containing two approximate, flat, rounded tubercles; 

 tip of body rounded, with a low, broad swelling at each lower corner; 

 the stigmal plates are approximate, each with three short slits, point- 

 ing toward those of the opposite plate. 



From melons in Hawaii; No. 8478. 



Rhagoletis suavis Loew. 

 (Plate V, figs. 94-96.) 



Body much the largest near the tip ; head small, bilobed, ea«h lobe 

 with minute antenna; two stout, blunt mandibles, and laterad of 

 them is a horny crest; anterior spiracles hemispherical, with about 25 

 lobes; surface of body smooth; beginning with the fifth segment 

 there is a basal, fusiform, much swollen area on the venter of each 

 segment, each transversely ridged and punctate; on the middle of 

 these segments is a transverse line extending down, on the sides; 

 dorsum of segments indistinctly divided into three transverse areas; 

 last segment with the anal area near the tip, not very prominent, but 

 with two prominent, approximate, smooth lobes; above the anal 

 area are two minute depressions; the stigmal field is slightly depressed, 

 the plates close together, each* with three narrow, straight slits 

 directed toward those of the opposite plate. 



From shuck of a butternut, Plummers Island, Md. 



Rhagoletis pomonella Walsh. 



(Plate V, figs. 83,84.) 



Body rather stout, tapering but little in front ; head broad, papilla 

 very small; two great hooks; anterior spiracles broad, with about 15 

 lobes; each dorsal segment from the third has a basal area of ridges; 

 each ventral segment from the fifth has a broad, basal, finiform, 

 swollen area, which is very minutely ridged; a transverse line on 

 middle of each ventral segment, and the apex of each segment with 

 an area of several transverse ridges; the lateral fusiform areas are 

 fairly distinct; the anal tubercle is moderately prominent, and 



