II 
ON THE AGAMIC REPRODUCTION AND 
MORPHOLOGY OF APHIS 
Transactions of the Linnean Society, vol. xxti., 1858, Pp. 193-220, 221-236. 
(Read November 5th, 1857.) 
$1. Preliminary Remarks—§ 2. The Viviparous Female, and the Development 0. the 
Pseudova—§ 3. The Oviparous Female, her Reproductive Organs and Ova—§ 4. The 
Development of the Pseudovarium in the Viviparous Female—§ 5. Summary; and 
Comparison of Germs and Ova—§ 6. Hypothetical Explanations of Agamogenesis— 
§ 7. Classification of the Phenomena of Agamogenesis. 
Part I 
S11. Preliminary Remarks 
“J’AL souvent pensé qu’on pourrait, dans l’histoire des sciences, 
désigner les époques par les principales découvertes. Par exemple, 
1665 seroit ’épogue de la Gravitation, 1789, Vépoque de la méthode 
naturelle en Botanigque, et, se parva licet componere magnis, les années 
1740 a 1750 seroient /’¢pogue des Pucerons.”+ 
Without, perhaps, being disposed to go so far as the enthusiastic 
French investigator of Plant-lice, no physiologist will deny that the 
experiments conceived and attempted by Réaumur, but first success- 
fully carried out by Bonnet, established facts of the highest import- 
ance, and raised questions which still disturb the very foundation of 
his science. 
But what were these great facts, established by Bonnet and his 
successors or contemporaries, Trembley, Lyonet, Degeer, Kyber, and 
others? 
If the moderns paid due attention to the labours of their pre- 
decessors, an accurate answer to this question should be found in 
1 Duvau, Mém. du Muséum, xiii. 1825. 
