FURTHER NOTES ON APHIDES 



159 



the fifth and without sensoria, its posterior half faintly imbricated ; 

 the fifth segment bears one sensorium near its apex and is imbricated 

 throughout its length; the sixth segment has a rhinarium with three 

 or four small sensoria below it, and is also imbricated. Cornicles 

 dark, much swollen in the middle, and narrowed at the base and 

 towards apex where they are narrowly reticulate. Cauda dark, 

 equal to more than half the length of the cornicle, thickly covered 

 with transverse rows of very short black bristles, and with four long 

 pale bristles on one side and five on the other. Hind tibia; 

 thickened for nearly three-quarters of its length and with many 

 sensoria ; apical portion narrowed, without sensoria, but with longer 

 hairs. Length, 2.0 mm. to 2.3 mm. 



Rhopalosiphian lactitcce, Kalt. Alate viviparous females were 

 common on gooseberry in the beginning of August at Swordale, 

 Evanton ; but unlike those taken on sowthistle the previous year 

 they exhibited melanic tendencies, the cornicles varying from 

 yellowish brown to black but being more frequently dusky brown 

 or black. Some of the specimens have been killed by the fungi 

 Empusa {Entoinophthord) aphidis, Hoff, and Empusa {Triplo- 

 sporiuni) Fresenii, Nowakowski, which Mr A. D. Cotton has kindly 

 identified for me. Apterous viviparous females, larvae, and nympha^ 

 of R. lactuca. occurred on sowthistle {Sonchus) at Stirkoke, Wick, 

 on 7th September, and I also took an oviparous female on goose- 

 berry at the same time. The following is a description of it, but 

 colour notes were not made from the fresh specimen. 





D 





Fig. II. 



Oviparous Female of RhopaloslphuDi lactuca, Kalt. 



A = Head and antenna magnified 31 times. 



B = Third segment of antenna magnified 128 times. 



C = Tibia of third pair of legs"! 



D = Cornicle -magnified 60 limes. 



E = Cauda J 





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