b PAPERS OX APHIDID^E. 



STEM-MOTHER.' 



First instar (before first molt). — General color dark nile-grcen; 

 head, beak, antennae, and legs ver}^ dark gray, almost black; corni- 

 cles very dark, small, and inconspicuous; eyes black; antennae 

 4-segmented. 



Measurements (from two specimens in balsam): Length of body, 

 0.49 mm.; width, 0.20 mm.; antenna, I, 0.0326 mm.; II, 0.0326 nun.; 

 Ill, 0.0896 mm.; IV, base, 0.0407 mm.; IV, filament, 0.0896 mm.; 

 total length, 0.2851 nmi. 



Described from two specimens. Tj'^j^es on two balsam slides in col- 

 lection of the Bureau of Entomology, U. S. Department of Agricul- 

 ture. La Fayette, Ind., 1910. 



Second instar (before second molt). — General color blue-green, the 

 head having somewhat of a grayish cast. Antennaa 5-segmented; the 

 three distal segments very dark, almost black; the basal segments 

 pale gray. Beak black at tip, reaching to coxse of the third ])air of 

 legs. Legs pale, excepting tarsi and distal portions of tibia;, which are 



black. Tips of cornicles black, small, and 

 inconspicuous as in the fii-st instar. 



Measurements (from two specimens re- 

 cently mounted in balsam): Length of 

 FiG.o.-Toxoptiramuhicnbcrijise: Eggs, body, 0.54 mm.; widtli, 0.245 mm.; an- 



Greatly enlarged. (Original.) -P ^ ^r,or» TT n nonn TTT 



tenna, 1, 0.0326 mm.; 11, 0.0326 mm.; Ill, 

 0.065 mm.; IV, 0.0489 mm.; V, base, 0.0489 mm.; V, filament, 

 0.114 mm.; total length, 0.342 mm.; cornicles, 0.0326 nam.; hind 

 tarsus, 0.0733 mm. 



Described from two specimens. Tjq^es on two balsam slides in 

 the collection of the Bureau of Entomolog}', U. S. Dei)artment of 

 Agriculture. La Fayette, Ind., 1910. 



Third instar (before third molt). — General color of body pale green, 

 eyes black. Antennae 5 segmented, entirely dusky, but darker near 

 the tips, a single sensoriunx at the end of IV and several at end of 

 base of V. Beak not reaching coxae of third pair of legs, the tip black. 

 Legs })ale greenish gray, exce})ting the joints and distal })ortions of 

 tibiae, which are dusky, and the tarsi, which are black. Cornicles 

 concolorous with body, excepting tips, which are dusky. 



Measurements (from two specimens recently mounted in balsam) : 

 Length of body, 0.88 mm.; width, 0.40 mm.; antenna, I, 0.0407 

 mm.; II, 0.0326 mm.; Ill, 0.125 mm.; IV, 0.0733 mm.; V, base, 0.0652 

 mm.; V, fdament, 0.14 mm.; total length, 0.4768 mm.; cornicles, 

 0.049 mm. 



Described from two specimens. Types on two balsam slides, in 

 the collection of the Bureau of Entomology, U. S. Department of 

 Agriculture. La Fayette, Ind., 1910. 



1 Color notes of the five instars of the stem-mother were made by Mr. Phillips 



