1118 The Zoologist — March, 1868. 



research, aud a long course of inquiry among men well calculated to 

 form a right conclusion. Let me advise, then, that while we keep our 

 eyes open in order to see for ourselves, and investigate the mystery, 

 we do not turn scornfully away from propositions which amaze, but 

 respectfully listen to the opinions of those who have acted as our 

 pioneers on this unknown track, and who have been busy in searching 

 for the truth upon a point which even now, at the end of twelve long 

 years, comes to us as a startling novelty. 



Alfred Charles Smith. 



Yatesbury Rectory, Calne. 



Notes on Aphides. By F. Walker, Esq., F.L.S. 



a 

 (Continued from S. S. 105&L) 



Genus 3. Rhopalosiphum, Koch. 



Typical species, Aphis Persicce, Sulzer. — Front flat between the 

 antennae, which are remote from each other at the base. Nectaries 

 clavale. In other characters like Siphonophora. 



A. Nectaries twice the length of the tail 1. Laclucce. 



AA. Nectaries thrice the length of the tail. 



A. Viviparous winged female wholly luteous. ... 2. Di'ibcridis. 



AA. Viviparous winged female with the head and thorax black. 

 a. Viviparous apterous female green or luteous. Antenna; pale. 



a. Viviparous winged female with the frontal tubercle gibbous on the inner 



side. Abdomen green or reddish, excepting the black spots. 3. Persicx. 

 aa. Viviparous winged female with the frontal tubercle not gib- 

 bous on the inner side. Abdomen luteous, excepting the 



brown spots 4. Ligualri. 



aa. Viviparous apterous female olive-grecu. Antenna? brownish 



black. 5. NymplnetB. 



The genus Rhopalosiphum is restricted by Passerini to the pre- 

 ceding five species, which belong to not less than four genera. 



1. R. Laclucce, Kaltenbach. — Kaltenbach mentions that his Aphis 

 Lactucae is erroneously cited by Koch as identical with Siphonophora 

 Lactucae. Passerini has observed it on Picris hieracioides and on 

 Cichorium endiva. Its oviparous form, so far as is known, appears 

 only on species of Ribes, where its occurrence is very irregular. A 

 wingless viviparous female, which 1 have described as a variety of 



