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MORDWILKO (A. K.). HtKOTOpblXTj CTapblXTj M HOBblX"b TnflX"b. 



[On some new and old species of Aphids.] — -tcPycCKOe 3hT0M0- 

 JlorHMeCKOe 0603p'feHie.» [Revue Russe <r Entotnologie], Petrograd, 

 XV, no. 4, 28tli March 1916, pp. 75-79. 



This paper, read at a meeting of the Kussian Entomological Society 

 in November 1915, deals further with a previously expressed view of 

 the author, that the regular migration of Aphids in a development 

 from the pol\^hagous habits of the species. The group Aphidea, of the 

 subfamily Aphidinae, provides evidence in support of this view, it 

 being possible to trace a line of forms which pass from polyphagous 

 conditions to regular migration from the so-called base plants (usually 

 the above-gi"ound parts of herbaceous plants) to the intermediate ones, 

 which in this case are various grasses. Such migrations and the 

 occurrence of forms entirely attached to some intermediate plants 

 were however unknown in the case of the group Anoeciea of the sub- 

 family Aphidinae or of the subfamily Pemphiginae. Though 

 Niisslin, while accepting this view, limited it to the subfamily 

 Aphidinae among the Aphididae, the author has recently discovered 

 evidence which makes it clear that this also occurs in the above-named 

 groups. In August 1915, he found a new species, Anoecia pshovica, in 

 the government of Pskov on the roots of grasses, the sexual form of 

 which breeds on the roots, the eggs also hibernating there. Thus in 

 the genus Anoecia one species, A. corni, ¥., migrates from various species 

 of Cornus to the roots of grasses, while the other, A. jjskovica, is entirely 

 a root-frequenting species. It is therefore suggested that these 

 Aphids originally occurred both on trees and grasses and subsequently 

 split into more specialised forms, some of which became exclusively 

 associated wath one kind of plant, the others becoming migratory. 

 The same phenomenon has also been recently proved to occur in the 

 case of the group Fordea of the subfamily Pemphiginae, some species 

 of the genus Pemphigellus migrating from Pistacea to roots of grasses, 

 while others are entirely attached to such roots {Forda, Paracleius). 

 Although the author has previously always separated Forda and 

 Pemphigellus into two groups, they possess great similarities, par- 

 ticularly the w^inged forms of Forda and the winged sexuparae of 

 Pemphigellus. He therefore now places Fordea, with its subdivisions, 

 Fordina and Rectinasina, as a third, natural group of the subfamily 

 Pemphiginae, the other two being Pemphigea and Schizoneurea. 



This paper also describes Rectinasus shelkovnikovi, sp. n., from an 

 ant-hill in the mountains of Ehsavetpol (Transcaucasia), which closely 

 resembles R. bucktoni, Theo., found in termite nests in Algiers. Notes 

 are also given on the differences between the migratory form of Tetra- 

 neura ulmi, L., and T. rubra, Licht. The former has been recorded 

 as T. zeae-maidis, Duf., T. boyeri, Pass., and T. coendescens, Mordv., 

 and the latter as T. coerulescens. Pass. A representative of the group, 

 Trichosipha hiwanae, Perg., has been found in South Ussuria at the 

 ends of oak shoots. This group also occurs in Ceylon, Java and 

 Japan. The wide distribution of Aphis rnaidis. Fitch ( = avenae, Kalt., 

 nee F., nee Mordv.), which is found in Europe, Caucasia, Siberia, Japan, 

 Java, North America, Africa, and Australia, is due to the similarly 

 extensive distribution of the grass, Panicum crus-galli, which is one of 

 its food-plants. 



