xcviii THE BEGINNINGS OF LIFE. 



I will, therefore, classify, as well as possible, the various 

 methods of reproduction that have been recorded as occur- 

 ring amongst one or other of the Ciliated Infusoria. But it 

 should be understood that although particular modes of 

 reproduction may be very frequently met with in individuals 

 having a given form, on the other hand the greatest lati- 

 tude is possible. Different representatives of any supposed 

 species may, occasionally, under the influence of different 

 external or unusual internal conditions, produce organisms 

 either similar or dissimilar to themselves by five or six dis- 

 tinct methods. 



Modes of Reproduction amongst Ciliated Infusoria. 



I. Reproduction by means of Fission. 



A. Animal in the free state. 



Fission may be either longitudinal, transverse, or 

 oblique in its direction ; though individuals of the 

 same species may occasionally divide in different 

 directions. 



a. Animals in their adult or mature condition 



this being most frequently the case. 



b. It may occur even in young embryos pro- 



duced from fission of pre-existing in- 

 dividuals in an encysted state ; e. g., in 

 young thus produced, of Stylonichia pus- 

 tulata, which closely resemble Trichoda 

 lynceus (Cienkowski). The creatures so 

 produced occasionally encyst themselves 

 before undergoing any further develop- 

 ment. 



B. Animal in the encysted state. 



a. Production of embryos which are more or 

 less similar to the parent. 



