314 



THE ZOOLOGIST. 



68. Rhopalosiphum ribis, Linn. 

 I have not been able to discriminate between the parasites of 

 this species and those of Myzus ribis, ante. 



69. Rhopalosiphum nymphece, Linn. 

 Walker states that Allotria erythrocephala saves the white 

 water-lilies from almost entire destruction by this Aphid over 

 large surfaces of the Thames and other ornamental waters. It 

 is, however, a little obscure both if this Cynipid be considered 

 hyperparasitic, like at least the majority of its genus, upon some 

 unknown Aphidiince, and if it be the unrecognisable species 

 described by Jurine (Nouv. Meth. pi. xii. gen. 40), or that of 

 Hartig (Germ. Mag. ii. p. 199), which is synonymised by Cameron 

 with A. victrix, Westw. Kieffer has found a very simple ex- 

 pedient by redescribing it as A. pusilla, Kief. ! The Dacnusid, 

 Gryocampa affinis, Nees, recorded from this Aphid by Gaulle 

 (Cat. 871), in reality doubtless emerged from some leaf -mining 

 Dipteron. 



70. Rhopalosiphum ligastri, Kalt. 

 From Aphis ligustri Kirchner bred (Cat. 30) Allotria erythro- 

 cephala, Htg., and Gaulle mentions the same species (Cat. 27) 

 under the name A. victrix, Westw. 



71. Rhopalosiphum berberidis, Kalt. 

 From this species Gaulle (Cat. 104) records the Italian Chal- 

 cid, Chrysolampus (Sphegig aster) pedunculiventris, Spin. 



72. Rhopalosiphum dianthi, Schr. 

 Curtis (Farm. Ins. 73) vaguely says that his Aphidius rapce 

 (= A. brassicce, Marsh.) preys upon the " turnip aphides," of 

 which he describes three species, but all these are synonymised 

 under the present species by Buckton (Mon. Aph. ii. 15). The 

 former remarks that several generations of the parasites are 

 evolved in a single summer, adding that they are so common 

 that he scarcely ever noticed a plant infested with these Aphids 

 where some of their dead and horny shells could not be observed. 

 A Proctotrypid, his Ceraphron {Lygocerus) carpenteri, and two 

 Chalcids, Asaphes vulgaris, Walk., and Coruna clavata, Curt., he 

 describes as parasitic through the Aphidius. 



(To be continued.) 



