A KEY TO THE GENERA OF THE SUBFAMILY 

 APHIDINAE AND NOTES ON SYNONOMY. 



By H. l-\ Wilson, 

 Oregon Agricultural College. 



The following paper is not as complete as the author would 

 like to have it as type species of four recently formed genera are 

 not available. Several attempts have been made to secure the 

 desired species without success and as there does not seem to 

 be much chance of securing them in the near future copies of 

 the original keys are included in this paper. All of them were 

 made by Del Guercio and three of them are given as a division 

 of the so called genus Aphis. 



The first three are given in Rcdia (vol. 4, pp. 190-192, 1907) 

 with the following key. 



1. I'cmiiic partenogen'uiic attire cd alatc sprovvistc di codetta o con 



qiiesta affatto rudimeutale. 



Gen. AxuR.vPHis Del Guercio 



(Sp. tip. Aphis pyri Koch). 

 Fcmminc attere cd alate con codetta distinta 2 



2. Codetta costantamente pin carta dei sijoni. 



Gen. Aphis Linne 

 (S]). tip. Aphis sambuci L.) 

 Codetta conslantamente cguale, o pin Innga dei sijoui o. 



3. Codetta piu liuii^a dri sifo)ii. 



(kn. URAnns Del Guercio 



(Sp. tip. Aphis gcnistae Kalt.) 

 Codetta del I a stessa lunghezza dei sijoni. 



Gen. MicKOSiPiiON Del Guercio 



(Sp. tip. Aphis tormentillae Pass.) 



The fourth was published two years later (Rivista di patolo- 

 gia X Vegetale anno IV Num. 11. Agosto 1909. pp. 4-5.) This 

 species is given as the dividing line between Aniiraphis Del 

 Gtiercio and Myziis Passerini. 



A. Codetta verricuforme, rudimentale o nulla. 



I. Femmine attere con tuhercoli frontali nulli, in ogni caso evident- 



emrnte piu corli delta nieta delta fronte; antcnne corte col 

 prima articolo subeguale al secondo. 



Gen. Anikaphis Del Guercio. 



II. Feniinc attere con tuhercoli frontali piu lunghi delta meta del 



niargine delta fronte fro essi conipressa: prima articolo del 

 antcnne, che sono lunghe, due volte piu lungo del secondo. 

 Gcii. Mac'ciii ATiKi.iA Del Guercio. 

 A A. Codetta hen distinta 



Gen. AIyzus Passerini. 



3M 



