120 THE CANADIAN ENTOMOLOGIST. 



the middle, thence truncate to the tip, where there is a short retrorse spine. 

 Tibia same width as palae and )4 as long. 



Length 5 mm. -5)^ mm. Boone Co. and St. Louis Co., Mo. July 

 and November. 



This species appears to resemble Corixa (Arciocorisa 1) acuminata 

 Uhl., but the structure of the male palae, which are quite unlike those of 

 any other species in the group, together with the shape of the head in the 

 male, the minute strigil, and the short lenticular pronotum, sharply sets it 

 off from other species. The presence of a frontal fovea in the female is 

 also extraordinary, and together with the points mentioned above seems 

 to warrant separating the species from its congeners in a new genus, for 

 which the name RAMPHOCORIXA is proposed, and of which the 

 following may stand as a diagnosis : 



RAMPHOCORIXA, n. gen,— Allied to Ardocorisa WaIlen.,from 

 ivhich it differs ifi the form 0/ the male palœ, strigil and shape of head. 

 Differs from Glœnocorisa Thoms, in the absence of bristles atnong the 

 palar pegs, Pro?iotum lenticular rastrate. Head of male sharply 

 acuminate, with fovea acorn-shaped, ^ pake dor sally, deeply cleft, much 

 longer than tibia, terminated by a long serrated spine; femur with a large 

 stridular area of minute spines, Strigil minute. Fifth, sixth and 

 seventh tergites divided i7t the male. Asymmetry of male dextral. 

 Fe?nale pake cultrate with a short retrorse terminal spine ; face of ^ 

 foveate. 



Explanation of Plate IV. 



Fig. I. — Yjggoi Ramphocorixa balanodis, x 34. The dorsal cup is 

 affixed to the carapace of the crayfish. 



Fig. 2. — First instar, ventral aspect, x 82. A = the pala or first 

 tarsus, X 240. 



Fig. 3. — Third instar, dorsal aspect, x 24, showing the beginning of 

 the wing-pads. The setae of the legs and body are omitted. 



Fig. 4. — Fifth instar, dorsal aspect, x 10. The wing- pads have 

 grown beyond the thorax and» are covered with downy hair. Cilia of 

 abdomen and legs omitted. 



Fig. 5. — Frontal aspect, head of male, x 20. 



Fig 6. — Pala of male, X51, viewed from inner upper angle. 

 F = femur; T = tibia; P = Pala or tarsus; A = row of pegs; B = stridular 

 area ; Q = diagrammatic section of pala marked X. 



Fig. 7. — Pala of female, x 68. 



Fig. 8. — Antenna x 68. 



