70fi GEOFFREY LAPAGE 



quontly ingested, but in most cases failed to digest, other 

 individuals of their own and also of other species (A. limax). 



2. In some cases, an amoeba, ^vhich had ingested another, 

 might itself then be ingested by a third amoeba ; and these 

 three might then be taken up by a fourth amoeba, so that 

 remarkable figures, suggesting concentric fissi(m, resulted. 



B. The victims were usually ingested while they were rounded 

 off or sluggish, and, after extrusion, usually failed to resume 

 their activity, although most of them developed contractile 

 vacuoles and some showed tentative amoeboid movements. 

 A few recovered their normal activity and resumed normal life. 

 Amoebae, after extrusion by one amoeba, were often taken up 

 again by other amoebae. 



4. In one case an Amoeba \- e s p e r t i li o was observed to 

 chase and enclose an Amoeba limax, but the Amoeba 

 limax subsequently escaped again. 



5. The ingested amoebae may easily be mistaken for endo- 

 genous buds, but there is less danger of their being mistaken for 

 parasites. 



6. No trustworthy evidence was found as to the nature of the 

 stimulus which caused the adoption of these habits, but the 

 question is discussed. 



Literature. 



1. Buck, Emil (1878). — " Einige Rhizopodenstudien "', ' Zeitschrift fur 



wisseuschaftliche Zoologie ', Bd. 30. 



2. Biitschli, O. (1887-9). — Protozoa in Bronn's ' Thierreich ', Leipzig. 



3. Calkins, Gary N. (1904-5).^ — " Evidences of a sexual cycle in the 



Life-history of Amoeba proteus ", ' Archiv fiir Protistenkunde ', 

 Bd. 5. 



4. Carter, H. J. (1863). — " On Amoeba princeps and its reproductive 



cells ", ' Aimals and Magazine of Natural History ', vol. 12, 

 p. 30. 

 4rt. Ibid., vol. 18, p. 223. 



5. Chatton, Edouard, and Brodsky, A. (1909). — " Le parasitisme d'une 



Chytridinee du genre Sphaerita (Dangeard) chez Amoeba limax 

 (Dujardin) ", ' Archiv fiir Protistenkunde ", Bd. 17. 



6. Collin, Bernard (1882). — " Etude monograiihique sur les Acinetiens ", 



' Archives de Zoologie Exijerimentale et Generale ', tome 51, 

 pp. 1-457. 



