26 
BULLETIN 100, U. S. DEPARTMENT OF AGRICULTURE. 
ductive organ white, when extended about as long as antennal joint IV. Beak pale 
yellow, extending a little beyond the first pair of coxae. Sterna and apical half of 
the underside of the head dark brown. Very often one or more of the dusky abdominal 
spots are absent. Measurements: Length of body, 1.39 mm. ; width of body, 0.69 mm. ; 
wing expanse, 4.10 mm.; cauda, 0.049 mm.; antennal joint I, 0.051 mm.; joint II, 
0.058 mm.; joint III, 0.362 mm.; joint IV, 0.238 mm.; joint V, 0.240 mm.; joint 
VI, 0.114 mm.; filament, 0.134 mm. 
Described from four specimens collected at San Jose, Cal., in 1912. 
Fig. 13. — Monellia caryx: Winged male, a, Left antenna. (Original.) 
THE LITTLE HICKORY APHIS (Monellia caryella Fitch). 
Aphis caryella Fitch, [First] Report on the noxious, beneficial, and other insects 
of the State of New York, Albany, p. 163-165, 1855. 
Callipterus caryellus Fitch, Third report on the noxious and other insects of the 
State of New York, Albany, p. 448-449, 1856. 
Monellia caryella, Oestlund, Geol. & Nat. Hist. Survey Minn. Bui. 4, p. 45, 1887. 
HISTORY OF THE SPECIES. 
The little hickory aphis was first collected in New York State by 
Dr. Asa Fitch, previous to the year 1855. The following is Fitch's 
original description : 
The Little Hickory Aphis (Aphis caryella) is pale yellow with white antennae which 
are alternated with black rings, the wings are transparent and without spots, their 
veins slender and pale yellow, the legs yellowish white to their ends. Length 0.12 
to the tips of the "wings. The abdomen is depressed, egg-shaped, its apex slightly 
