xiii, b, 5 Haughivout: Flagellated and Ciliated, Protozoa 231 



substance may be seen in the cytoplasm following the first nu- 

 clear division and states his belief that they represent the reduc- 

 tion bodies I have already mentioned. He has not observed 

 them in the process of formation. 



Following the multiple division of the nucleus, cytoplasm col- 

 lects around each nucleus, and the small cells thus formed break 

 from the peripheral ring and enter the centrally situated food 

 vacuole, which would then appear to become something in the 

 nature of a brood chamber. The substance within this vacuole 

 seems to be gradually consumed by the cells, which grow in size. 

 Next the cyst wall weakens, the young organisms burst out and 

 swim off as trophozoites, measuring 4 to 5 //. in length by 3 jj. 

 in width, each equipped with an anterior flagellum, a nucleus, 

 and a blepharoplast. Gradually these young forms develop addi- 

 tional flagella and the other organelles characteristic of Tricho- 

 monas. During this series of developmental changes it would 

 appear that the organism might come to resemble Wenyon's 

 Macrostoma mesnili. 



It is at this stage that Hadley says he has evidence of conjuga- 

 tion between two or three or even four individuals. This con- 

 jugation of more than two individuals would constitute something 

 of a departure from the process usually observed in the Protozoa 

 where syngamy occurs (when it is not autogamous) between 

 two individuals only. It is hard not to regard the union of three 

 or even four individuals under such circumstances as being 

 wholly fortuitous and probably unproductive of results. At per- 

 iods of sexual maturity in the Protozoa it is not infrequently 

 observed that the ectoplasm of the organisms becomes sticky, 

 so that they have a tendency to adhere in pairs if they blunder 

 against each other. This is strikingly seen in the conjugation 

 of Paramcecium caiulatum; and it is not very unusual when 

 epidemics of conjugation occur in a culture, as they frequently 

 do, to see three or four irregularly attached individuals swim- 

 ming about in a clump. Usually the matter adjusts itself with 

 the aid of the ciliary currents of the animals, which tend to 

 bring them into the proper position for carrying out the process 

 of conjugation. 



If conjugation or copulation of these flagellated individuals 

 takes place, as Hadley suspects may be the case, it seems to be 

 a process of either endogamy or exogamy, depending, of course, 

 upon whether union took place between cells derived from the 

 same or from different cysts. In that case Hadley's autogamy 

 would fall and the process of nuclear reduction he suggests 



