Mr. F. Walker's Descriptions of Aphides. 43 



other respects it is very different from R. Radula and its allies. 

 It seems far more correctly placed in close connection with R. 

 Guntheri and R. glandulosus. In the ' Compend. Fl. Germ/ (ed. 2) 

 it stands between R. Guntheri and R. Menkii. Its scabrous stem 

 and very different panicle distinguish it from the former, and the 

 very different prickles of the stem from the latter. From R. glan- 

 dulosus, to the variety Lejeunii of which Mr. Bloxam thinks it 

 is allied, the remarkable armature of the stem and the broad 

 pyramidal divaricate panicle appear to separate it. 



VI. — Descriptions of Aphides. By Francis Walker, F.L.S. 



[Continued from vol. i. p. 454.] 



Fourteenth Group. 



The species of this group feed on grasses and rushes ; they 

 have rather flat bodies, short feelers and legs, their nectaries 

 hardly rise above the surface of the body, and they very rarely 

 occur in the winged form. 



26. Aphis Glyceric. 



A. Glyceric, Kalt. Mon. Pflan. i. 113. 87. 



The viviparous wingless female. This insect feeds on the leaves of 

 Glyceria fluitans, floating-grass, during the summer and autumn. 

 It is yellowish green, hairy, rather flat, with slight transverse 

 ridges, and gradually increases in breadth from the head till near 

 the tip of the abdomen : there are two dark green, broad, indi- 

 stinct stripes along the back : the front is concave on either side 

 and slightly convex and notched in the middle : there are no 

 tubercles at the base of the feelers, which are setaceous, yellow, 

 and less than one-third of the length of the body ; their tips are 

 brown ; the fourth joint is much shorter than the third ; the fifth 

 is as long as the fourth ; the sixth is longer than the fifth ; the 

 seventh is as long as the sixth : the eyes are dark brown : the 

 mouth is yellow and reaches the middle hips ; its tip is brown : 

 the legs are yellow and rather short ; the feet and the tips of the 

 thighs and of the shanks are brown ; the shanks are straight. It 

 has a soft velvet-like appearance, and varies much in colour, being 

 either deep green, or pale green, or yellow, or sometimes mottled 

 with these colours ; or it has a reddish tinge, or is reddish yellow, 

 or almost brown ; it is adorned with rows of little black dots. The 

 young ones are light fresh green, having the head and the limbs 

 almost white. 



The viviparous winged female. This is very scarce : the head 

 and the disc of the chest are brown : the feelers are rather more 



