278 APPENDIX 



water and emitting long pseudopodia on all sides (3 ; Plate ii. Fig. 25). 

 After ingesting food tlie animals were found by Hieronymus to encyst on 

 the surface of plants, and he states that division of the nuclei follows the 

 encystment. But in the majority of cases a different process was 

 observed to follow the emergence from the encysted state. The proto- 

 . plasm puts out short pseudopodia and divides up forthwith, by successive 

 bipartition or by simultaneous division, into small uninucleate amoebae, 

 the products of division being equal in number to the nuclei contained 

 hi the original cyst. The division into the ultimate products is usually 

 complete in a few minutes from the emergence of the protoplasm. The 

 small amoebae so found may creep about and ingest small algae or 

 bacteria before passing into the encysted form. While this is the usual 

 course, Hieronymus describes cases in which the process of division ceased 

 after one or two partitions had occurred, and was followed by a stage of 

 feeding and subsequent encystment. Further evidence of such cases 

 would be desirable, and it seems possible that two separate phases of the 

 life-history may have been here confused ; but it is clear that the fission 

 of the multinucleate body into uninucleate products represents a phase of 

 reproduction comparable with that which occurs in many other protozoan 

 life-histories, and of which we had no previous evidence in Chlamydowyxa. 



Spore-Formation. The process of spore-formation has been most fully 

 observed by Penard in G. montana, 1 but stages of it have been seen by 

 Archer and Hieronymus in C. labyrinthuloides. The contents of an 

 encysted form are segregated by simultaneous fission into a number 

 (20 to 40) of equal (Fig. 2, a) (? sometimes only sub-equal (Fig. 2, &)) 

 divisions. These are at first continuous with their neighbours by proto- 

 plasmic strands (3 ; Plate i. Fig. 7), but later they separate into bodies 

 which become spherical and each secretes a cellulose wall. They are 

 liberated by the opening of the cyst (in a manner not observed). Penard 

 finds that these secondary cysts, or spores (Fig. 2, c), as we may call them, 

 measure in C. montana 18 /u, in diameter, and that each contains two 

 nuclei lying opposite one another in a meridian of the sphere. 2 In some 

 cases the contents of the spores were found to have emerged as naked 

 masses of protoplasm, containing the chromatophores and refracting 

 corpuscles characteristic of the species. Each acquired a flagellum (or two 

 flagella ?) about equal to the body in length (Fig. 2, d\ and for some 

 moments (" pour quelques instants ") was actively motile. Some of these 

 flagellate bodies appeared to possess one nucleus, others two or even 

 three, and there was an indication of their fusion in pairs (" lorsque les 

 petits flagellates viennent & se rencontrer, ils peuvent se fusionner en un 

 seul," p. 331). Some continued to show a slow movement for twenty- 

 four hours, but ultimately they died under the cover-slip. 



It would be premature at present to make any dogmatic statement as 



1 It was only for a few days that Penard succeeded in observing this stage in the 

 life-history. It occurred in March, in the neighbourhood of Geneva. 



2 Penard's account of the subsequent history of these bodies is of great interest, 

 but, owing to the sparseness of his material and the rapidity of some of the events, 

 he was unfortunately not able to observe the stages with precision. With this 

 reserve, an outline of his results is here given. 



