286 FRED. V. THEOBALD 



11. Aphis pomonella, Theobald (fig. 11). * 



Canad. Ent., xlviii, p. 262, fig. 9, 1916. 



British East Africa : Nairobi (T. J. Anderson). 



Food-plant. — Apple. 



Closely related to Aphis pomi, but can at once be separated by~(l) the different 

 antennae and (2) by the shorter cornicles. A. pomi has more sensoria on segment 



rrtnss-EES^ss^iTagpc: 



Fig 11. Aphis pomonella, Theobald, alate $: A, head 

 and antenna ; B, cornicle ; C, cauda. 



three and more irregularly disposed, and also some on segment four. Some American 

 Aphidologists have pointed out to me that this may be only a variety of Aphis 

 pomi, De Geer. 



12. Aphis pheidole, Theobald. 

 Ent. Record, xxviii, p. 37, 1916. 



Found associated with ants (Pheidole sp.) at Mwengera, N.-W. Rhodesia, ix. 1913. 



13. Aphis acetosae, Koch (non Linn, Fabr, Buckton) (fig. 12). 

 Koch, Die Pflanz., p. 145, figs. 197, 198 (1857). 



Egypt: Ghezireh, 3.iii.09 and i.iv.09 (F. G. Willcocks). England: Wye, 

 Kent, 7.vi.l5 (Theobald). Germany (Koch). 



Food-plants. — Rumex spp.* and Papaver spp.f 



Linnaeus' and Fabricius' Aphis acetosae in the alate female has two dark bars 

 across the abdomen and also the Aphis acetosae of Buckton.} The specimens from 

 Egypt and those I found at Wye show no trace of this ornamentation. These agree 

 closely with the Aphis acetosae of Koch. I append a detailed description of this 

 species, which must receive a new name, and I propose acetosella. 



Alate viviparous female (Rumex form). — Head shiny black to very deep shiny 

 olivaceous ; eyes dark. Antennae black ; first segment wider than, but of the same 

 length as, the second ; third longer than fourth but not quite so long as sixth, with 

 13-18 sensoria over its whole length ; fourth longer than fifth, with 2-5 sensoria, 

 three usually placed basally ; sixth as long as 4 + 5, its basal area about half as 

 long as the flagellum ; the usual sensoria on fifth and sixth ; all segments from 

 third imbricated. Proboscis reaching to second coxae; green, with black apex. 

 Pronotum green in front and behind, black between. Thorax shiny black. Abdomen 

 green, very shiny ; some with a dark green median line, others with the whole 

 dorsum mottled with deeper green ; on the sides of the abdomen are three dark 



* Syst. Nat., ii, 7340. 



t Ent. Syst., iv, p. 220 (1794). 



% Monog. Brit. Aphid., ii, p. 80, pi. lxii, pp. 5-7 (1877). 



