SOME OBSERVATIONS ON ACINETARIA. 375 
and, in fact, I was only once able (text-fig. 7) to follow the 
process in the living individual ; but if the cilia, as is the case 
in the normal bud, disappear at the end of a couple of hours, 
it might be very difficult to distinguish the later stages of 
process (2) from those of process (1) (text-figs. 6 and 7). 
TEXT-FIGURE 7.—A. papillifera, conjugation between a free 
ciliated bud and a fixed form. Ma., Me. Macronucleus. Jf. 
? Micronucleus. S¢. Stalk. (Zeiss 2 mm. apoclir., comp. oc. 6.) 
IV. ConcLusions. 
(1) The Tinctin-kérper of Acinetaria are generally frag- 
ments of the ingested nucleus of their prey. 
(2) Conjugation in Acineta papillifera agrees in all 
essentials with the process occurring in the Ciliate Infusoria, 
and that described by Hickson for Dendrocometes para- 
doxus. 
It is possible that in those cases in which a fixed form 
cannot come into contact with another mature individual, a 
reorganisation of the nuclei may be effected associated with 
