WALNUT APHIDES IN CALIFORNIA. 



17 



oval gray transverse spots on the fifth segment, which are separated by a space equal 

 to their length. Cornicles pale yellow, about as broad at the base as long, very much 

 as in the winged female. Cauda pale yellow, globular, not quite as long as the hind 

 tarsus. Sexual organ pale yellow. Beak pale yellow, slightly exceeding the fore 

 coxas. Sterna black. Sensoria transversely oval, situated in an irregular row as 

 follows; joint III, 11 to 16; joint IV, 5 to 7; joint V, 4 to 5; joint VI, 2 besides usual 

 terminal. * 



Measurements: Length of body (average), 1.47 mm.; width of body (maximum), 

 0.48 mm.; expanse of wings (average), 4.20 mm; antenna, joint I, 0.05 mm.; joint II, 

 0.04 mm.; joint III, 0.34 mm.; joint IV, 0.12 mm.; joint V, 0.12 mm.; joint VI, 0.08 

 mm. ; filament, 0.03 mm. ; cornicles, 0.05 mm. 



Fig. 8.- 



- Chromaphis juglandicola: Winged male (appendages of left side removed), a, Left antenna. 



(Original.) 



Described from many individuals collected in 1911 and 1912 at 

 San Jose, Cal. 



Both the male and the winged viviparous female when disturbed 

 have a habit if jumping psyllid-like into the air. Their flight is 

 generally in the form of a long spiral, and when disturbed they fly in 

 an upward direction. 



EGG DEPOSITION. 



/ 



As mentioned before, the first sexual females of the year remain 

 longer on the leaves after they have reached the adult state than 

 those developing later. In 1911 eggs were not observed in the 

 field until September, or seven weeks after the first appearance of 

 sexual females. In 1912 some eggs appeared in August. This long 

 period between the first appearance of the sexed females and the 

 40859°— Bull. 100—14 3 



