IOWA ACADEMY OF SCIENCES. 211 



DELTOCEPHALUS MINIMUS N. SP. 

 (Plate xxiv, Fig. 4.) 



Form and color of debilis, but less than half the size; length 

 of vertex more variable even than in that species; the smallest 

 species in the genus; length, female, 2.75 to 3 mm.; male, 2.25 

 to 2.50 mm. 



Vertex very variable in length, usually convexly and acutely pointed in 

 the female, longer than the pronotum; rouadingiy rectangular in the male, 

 about equaling the pronotum; front strong; similar to cfefti/is broader on the 

 clypeus; clypeus broad, one-half longer than wide; lora? broad, nearly 

 semi-circular; genas much narrower than the eyes, lateral margin short and 

 straight. 



Genex-al color like that of debilis; vertex, margins of the pronotum and 

 scutellum yellowish-green; disk of the pronotum and basal part of the ely- 

 tra dark green; apical portion of the elytra ligater. Below, front fuscous 

 with lighter arcs, rest of face greenish; tergum and venter greenish or 

 fuscous, varying to black; legs usually distinctly black below. 



Genitalia: Ultimate ventral segment of female broad; posterior margin 

 roundingly produced from the lateral angles, narrowly arcuated and notched 

 medially, black tipped; py gofers nearly twice as long as width at base, 

 equaling the black ovipositor; male valve large, triangular; plates broad, 

 convexly pointed, three times the length of the valve, usually a dark spot 

 beyond the middle of each. Described from numerous examples. 



Larvce: Small dark green forms with acutely pointed vertices and black 

 faces and eyes; vertex convexly, acutely pointed; body long, tapering from 

 eye back to tip of abdomen; hairs on abdomen distinct; green above, ver- 

 tex lighter, ocelli black. Below, all dark fuscous to black in the later 

 moults, especially noticeable on legs. 



This very small and distinct species occurred abundantly on 

 a patch of raw prairie adjoining the Adropogon field, where the 

 oculatus occurred so thickly, and was found at the same time 

 and in the same stages as that species throughout the season, 

 but did not occur on the isolated Andropogon. Sporobolus 

 heterolepis and the Stipa were very plentiful, where they were 

 most abundant, either one of which would harmonize well with 

 its green color. 



DELTOCEPHALUS MELSCHEIMERI FITCH. 



(Plate xxiv, Fig. 1.) 



AmbJycephalus melscheimeri Fitch. Homop. N. Y. State Cab., p. 61. 

 Deltocephalus dehilis Osborn. Bull, Iowa Exp. Sta. No. 13, p. 100; No. 20, p. 714. 

 DeltocephalKS afflnis Gillette and Baker. Hemiptera of Colorado, p. 84. 

 Deltocephalus auratus Gillette and Baker. Hemiptera of Colorado, p. 8.5 (Female). 



This is a slightly smaller species than debilis and with more 

 general fuscous markings. 



Vertex one-half longer on middle than at eye, width between eyes 

 greater than length; obtusely, slightly roundingly angled. Front narrower 



