Febl-uary, '17] YINGLING: APHID EGGS IN TEXAS 223 



Isle of Pines . . . 



Java 



Natal 



Paraguay 



Portugal 



Santo Domingo. 



Senegal 1 



Seychelles 1 



Siam 1 



Sudan 1 



Turk's Islands 1 



APHID EGGS IN TEXAS (Lat. 30°, 30') 

 By Hal C. Yingling, College Station, Texas 



For some time the impression has existed that oviparous reproduc- 

 tion in aphids does not occur in the extreme southern portion of the 

 United States. To quote F. M. Webster (Bureau of Ent. Bui. No. 

 110), — "In the South, seemingly south of about latitude 35° to 36° 

 north, it has been impossible to find eggs of this (Toxoptera graminum 

 Rond.) and other species of aphidids in the fields." Other papers 

 have given the same impression, apparently based on the fact that no 

 eggs had been found and the assumption that the egg stage was unnec- 

 essary for hibernation in warmer climates. As practically all of Texas 

 lies south of 35°, the common impression has been that aphid eggs do 

 not occur except in the northern part of the state. 



On a collecting trip December 16, 1916, the writer found two rather 

 large clusters of aphid eggs with wingless aphids in the act of oviposi- 

 tion, all under normal conditions for the locality. The eggs were 

 packed closely together upon a single stem of dogwood (Cornus asperi- 

 folia Mich.), the two clusters being situated near the end of the twig, 

 about three inches apart. Wingless females alone were found, hud- 

 dled together on and around the masses of eggs, the weather being 

 rather chilly. 



The material was turned over to Prof. F. B. Paddock of the Texas 

 Agricultural Experiment Station, who identified the aphid and host, 

 also making a brief studj^ of the habits. The aphid compares very 

 favorably with the description of Schizoneura corni Fab. 



Professor Paddock had the good fortune to watch the deposition of 

 an egg by one of the females, the process being resumed when the 

 aphids were introduced into the warm laboratory. The female backed 

 up to the egg cluster to place the egg with the others, the whole 

 process taking about forty-five minutes for completion. During this 

 time the middle legs were held tightly folded under the body. The 

 egg was deposited with its long axis perpendicular to the surface of 

 the bark, but soon turned over and rested in a horizontal position. 

 The material covering the egg was viscous enough to enable the aphid 

 to use the egg as an anchor while placing the next egg. 



