20 



PAPERS ON APHIDID^. 



DESCRIPTIONS. 



WINGLESS STEM-MOTHER. 



General color gamboge. Head and body bearing numerous tuber- 

 culate capitate hail's or spinolike hail's in a more or less regular order, 

 as follows: Head mth three in a row on each side of the dorsal 

 median line; two pairs, one not always conspicuous, ])rojectiiig from 

 the front, and a single one on each side near the posterior border; 

 prothorax with two near anterior border and six along the posterior 

 border; remainder of body bearing two rows of capitate hairs on 

 each side of the dorsal median line, the tubercles bearing these two 

 rows being confluent, so as to present the appearance of a single row 

 on each side, with two hairs to each tubercle; laterad of these are two 

 distinct rows of tuberculate hairs on each side. The tubercles on 

 the head and prothorax are dusky at their apices and the capitate 

 hairs are black; other tubercles are rimmed at base with a blackish 

 line, the apices and hairs being black. 



Eyes red. Antennae reaching about to the cornicles; segment III 

 longest, it being more than one-third longer than VI (base + filament), 

 the base and filament of VI subequal; segment III with 7 to 10, 

 usually 8, oval sensoria in a row, V and base VI with the usual distal 

 ones; segments I and II concolorous with body; III and IV pale, 

 but slightly darker than body color and with a faint brownish tint; 

 V becoming blackish towards tip, and VI black. Beak not quite 

 reaching coxae of second pair of legs. Legs paler than body color, 

 the tip of tarsus black. Cornicles as long as width at the base, 

 being about as long as antennal segment I, concolorous with body, 

 the basal rim and tip with a narrow blackish line, on border. Cauda 

 globular, concolorous with body, bearing a number of moderately 

 long unknobbed hairs. Anal plate conspicuously bilobed. 



Measurements made from two individuals, May 5, 1913, at La Fay- 

 ette, Ind., immediately upon {)lacing in balsam and before any 

 change of form occurred, are as follows: Length of body, 1,55 mm.; 

 width, 0.77 and 0.81 mm., respectively; length of spines, 0.078 mm.; 

 of tubercles, 0.05 mm.; length of cornicles, 0.0(51 mm.; width at tip, 

 0.035 mm.; antennal measurements as follows: 



