THE YELLOW CLOVER APHIS. 



25 



WINGLESS OVIPAROUS FEMALE. 



(Fig. 14.) 



Gcnoral color yellowish or}ui<];o to oran<j;(' when fully maturo. 

 Tho body is usually yollowish when tll(^ foiualc first roaches maturity, 

 but as the eggs, which arc of aii orange color, l)egiu to develop within 

 the body they show through the semitransparent skiu, giving the con- 

 spicuous orange color to the body. Head and prothorax pale yeUow, 

 inesothorax and metathorax var^-ing from ycdlow to orange accord- 

 ing to age since maturity. Dusky tuberculate areas conspicuous. 

 These and the black cajiitate liairs arranged as on the stem-mother. 



Eyes blackish or brownish black. Antennae not reaching to base 

 of cornicles; relative lengths of segments as in other forms; segment 

 III bearing 7 to 10 ovalsensoria in a row, and segments V and base of 

 VI with the usual distal areas; basal segments concolorous with 

 head, others gradually darkening toward apex. Legs pale yellowi.sh 

 except tarsi; proximal 

 halves of hind tibiae swollen 

 and bearing 25 to 40 in- 

 conspicuous, irregularly 

 placed, circular sensoria 

 (fig. 14, a). Cornicles and 

 Cauda concolorous with ab- 

 domen, often dusky at 

 margins. Cauda knobbed 

 as in other forms, but the 

 anal plate is rounded at 

 the tip and does not have 

 the slightest emargination 

 (fig. 14, h). 



Measurements: Length 

 of body (average), 1.8 mm.; 

 width, 0.86 mm.; cornicles, 

 antennal measurements as follows : 



Fig. U. -Tho yellow clover aphis: Wingless oviparous 

 fi'inale, iiiue|i enlarged, a. Hind tibia of same; 

 b, Cauda and anal plat<» of same, a, b, Oreally en- 

 larged. (Original.) 



0.061 mm.: hind tai-sus, O.I'M mm.- 



