1918] Baker — Another Toxoptera Feeding on Sedge (Homopiera; Apkididce) 89 



the second generation also. These forms are produced throughout 

 the summer in the different generations, but toward fall they ap- 

 pear in very small numbers and when the sexes are appearing very 

 few alate forms can be found. The alate forms either reproduce 

 upon the plant on which they developed or fly to other plants of 

 the same species. 



Fourth instar (pupa) . General color brownish black, the thorax 

 somewhat pinkish or whitish brown, otherwise colored as in the 

 apterous form. Antennae with the following measurements: Seg- 

 mentIII,0.208mm.;IV,0.16mm.;V,0.16mm.;VI(0.08+0.4mm.); 

 cornicles 0.192 mm.; antennal tubercles quite acute in front and 

 armed with short stout spines; vertex similarly armed. 



When cleared of the body fluids the abdomen and most of the 

 thorax appear to be almost transparent. The antennae, head, legs, 

 wingpads and cauda are dusky and the cornicles dark brown. 



Fifth instar (adult). General color deep brownish or purplish 

 black. Antennae somewhat lighter than the general body color. 

 Abdomen and cauda sometimes of a dark greenish color. Corni- 

 cles black, sub-cylindric, slightly constricted near the tip and dis- 

 tinctly flanged. Legs with the base of the femora and most of the 

 tibiae yellowish or whitish. Measurements and sensoria as given 

 in Table I. 



TABLE I. MEASUREMENTS OF ANTENNAE AND CORNICLES OF 

 THE ALATE VI VIP AR A. 



Segment 

 III. 



Segment VI. 



Cornicle. 



0.304 



0.304 



0.288 



0.304 



0.304 



0.304 



0.32 



0.288 



0.288 



0.304 



0.08 +0.4 

 0.09 +0.432 

 0.096+0.432 

 0.08 +0.448 

 0.096+0.464 

 0.08 +0.432 

 0.08 +0.448 

 0.096+0.432 

 0.096+0.432 

 0.08 +0.432 



0.24 



0.24 



0.24 



0.24 



0.24 



0.24 



0.24 



0.24 



0.224 



0.24 



