SANBORN : KANSAS APHIDIDE. 27 



the tender bark, whether it be in a crevice or exposed, as on the 

 water sprouts. The places most adaptable for them are on the 

 tender bark which is overgrowing a wound where a branch has 

 been pruned off. The secretion of the underground form is 

 more of a pulverulent nature, and is impervious to water. This 

 secretion on the aerial form grows out at the rate of 0.50 mm. per 

 week, as found by actual experiment, and on account of this 

 protection no parasites molest them as they do the less pro- 

 tected genera. 



Schizoneura lanigera Hausm. Plate II, fig. 7. 



Entire body chocolate brown after the bluish-white cottony 

 secretion is removed. Length of antennal joints : I, 0.03 mm. ; 



II, 0.05 mm. ; III, 0.09 mm. ; IV, 0.03 mm. ; V, 07 mm. ; 

 VI, 0.07 mm., including the unguis; latter alone, 0.01 mm. 

 A circular sensorium at the distal end of the fifth and the sixth 

 joints. Eyes black ; not hemispherical, as is normal, but small 

 and black, with three or four of the cornea appearing as large 

 and translucent ocelli. Ocular tubercles and ocelli absent. Beak, 

 0.36 ram. long, extending near to the second coxa. In the 

 very young larva the beak is equal to the body in length. 



Thoracic segments all similar and not characterized as lobes. 

 Legs short. Abdomen large in proportion to the anterior divi- 

 sions, and is about as broad as long. Honey-tubes almost ob- 

 solete, style not well developed, subobsolete, twice as wide as 

 long, 0.07 mm. long and 0.14 mm. wide. 



This form was collected with the winged form described. It 

 is gregarious and colonizes the sprouts, wounded places and 

 tender bark on the trunk and limbs, but is not found on the 

 leaves. 



Schizoneura corni Fab. Plate VI, fig. 38. 



Head black. Antennae dark and hirsute, about half as long 

 as the body ; length of segments : I, 0.054 mm. ; II, 0.07 mm. ; 



III, 0.198 mm. ; IV, 0.09 mm. ; V, 0.109 mm. ; VI, 0.145 mm., 

 including the unguis, which alone is 0.036 mm. ; total length, 

 0.67 mm. The sensoria are large and circular; about six on 

 the third joint, two on the fourth, two on the fifth, and one on 

 the sixth at the base of the unguis. The eyes are black ; ocu- 

 lar tubercles present ; ocelli present but not very prominent. 



