34 2 LEON AUGUSTUS HAUSMAN. 



similar mode of multiplication occurring among the Sporozoa. 

 As it occurs in Amoeba protects its course is as follows: The 

 individual encysts; the nucleus divides into several smaller 

 nuclei; these migrate to the periphery of the cell; the protoplasm 

 of the cell divides into as many equal portions as there are 

 nuclei; the cyst wall ruptures; and the nucleus-containing bits 

 of protoplasm emerge, each a complete Amoeba and an epitome 

 of its parent. In analogy with the spores of the Sporozoa these 

 were given the name, pseudopodiospores. More recently Calkins 

 ('05) has noted a method of reproduction in which the nucleus 

 produced by repeated division, gametic nuclei, whose fusion 

 resulted in other nuclei which became the nuclei of the smaller 

 individuals after the manner of the pseudopodiospores just men- 

 tioned. The young Amcebce soon assumed the form hitherto 

 called Amoeba radiosa; passed through this stage and became 

 the common Amoeba proteus. 



Another apparent mode of reproduction was observed by 

 Metcalf ('10). In this method the observer is of the opinion 

 that the sequence of events is: Mature individuals produce 

 globular masses of protoplasm, which are termed gemmules. 

 These develop flagella and assume a cercomonadoid form; later 

 they fuse by two and two, lose the flagella, and develop into adult 

 Amceboz. It is stated that possibly the life cycle of Amoeba 

 proteus may require a year or more for its completion, and may 

 exhibit during its course three, or even more, modes of repro- 

 duction. 



Schepotieff ('08, '09) states: "All of these examples suggest 

 that in the case of the Amoeba [proteus] the developmental cycle 

 may be completed in very different ways." 



It has been shown, as we have said, that Amoeba radiosa, 

 formerly regarded as a distinct species, is merely a stage in the 

 development of Amoeba proteus. It may be that this also is true 

 of such recognized species of Amoeba as villosa, princeps, diffluens, 

 etc. It is suggested elsewhere in this paper that the species 

 known as Amoeba guttula is but a developmental stage in the 

 cycle of proteus. Vahlkampf ('05) has shown that Amoeba Umax, 

 at least, is to be regarded as a distinct species. 



