APPENDIX D. Ixxxix 



three or four segments the division being cruciate while 

 others extended themselves in a linear series, with their 

 short diameters in a line. . . . Some of the divisions, instead 

 of sub-dividing, increased in size, producing a green cell 



much larger than the rest The mucus which formed 



around these cells was at first more or less definite in boun- 

 dary, but after segmentation had advanced to some degree 

 its outline was irregular, and at last quite indefinite. The 

 outer edge never possessed more solidity than the mucous 

 envelope of Cladonia gleocapsa.' Dr. Hicks has seen this 

 condition commence within the parent Volvox. He points 

 out its resemblance to that which occurs occasionally during 

 the growth of Pandorina and Stephanosphcera, and he 

 adds : ' There is also a striking analogy between these and 

 the segmenting gonidia of lichens, especially of Cladonia! 



Other additional modes of reproduction in Volvox are 

 described in Pritchard's ' Infusoria.' 



Mr. H. J. Carter believes that Euglence and Astasice are 

 closely related to the members of the genus Amoeba. He 

 has seen the actual transition of Astasicz into Amcebce, and 

 says 1 : 'Young Astasice are developed within the cells of 

 Spirogyra to a great extent ; and although they at first have 

 almost as much polymorphism as an Amaefia, still they retain 

 their cilium, and after a while assume the form and movements 

 peculiar to Astasia. I might here mention that on one occasion 

 I saw a large Amoeba with a long cilium, at one time assum- 

 ing the form of Astasia, and at another that of Amoeba, which 

 thus gives us the link between these two Infusoria 2 . The 



1 ' Ann. of Nat. Hist.,' 1856, vol. xvii. p. 115. 



2 I have observed this modification very frequently. Whenever the 

 Asinsia is hemmed in by opposing particles or fragments, it insinuates 

 itself between them and moves generally after the fashion of an Amoeba ; 

 but, as soon as it has freed itself from the obstacles, it resumes its 

 more active mode of locomotion. 



