MULTICONJUGATION IN BLEPHARISMA

¹ Arnold Biological Laboratory, Brown University, Providence, R. I.

A cytological and experimental study was carried out on conjugations involving more than two individuals of Blepharisma undulans. Attachment of the participants in a conjugating group occurs in a number of characteristic patterns. Regardless of the attachment pattern, nuclear changes occur in all members of a multiconjugant system. These changes are identical in nature and duration to those observed in normal paired conjugation, and occur synchronously in all participants of the system. The stocks of B. undulans used are found to be selfing, physiologically not differentiated into mating types. Multiconjugation can be induced by varying food supply and population density. The probability of autogamous processes in connection with multiconjugation is discussed.