xv, 4 De Leon: Balantidium Haughwouti 405 
occurring free in fresh waters in Connecticut, in the United 
States, but he says nothing regarding the possible source of the 
parasites. Haughwout(5) has briefly discussed the matter of a 
free-living stage in the life cycle cm Trichomonas and raised a 
question as to the identity of the organisms described by several 
authors as occurring free. 
METHOD OF FEEDING 
These animals are very voracious, continuing to feed, under 
the cover glass, almost up to the time of death. When feeding 
they move slowly and evenly forward, producing, by means of 
the adoral membranelles, a powerful current of water near the 
anterior end. This current simulates a whirlpool, the vertex of 
which points toward the oral depression. It is produced by the 
coordinated succession of rapid lashing movements of the mem- 
branelles and cilia from without oralward. This movement pro- 
duces to the eye the effect of a rotating peristome or the trochal 
disk of a rotifer. The current of water impinges on the oral 
vestibule at an effective angle at one side. There is a sideflow 
which leaves the depression on the opposite side much as is seen 
in the case of Vorticella. There apparently is little, if any, 
choice of food at the intaking — every object below a certain size 
is swept into the pharynx; the rest goes out in the sideflow. 
Such selection as there is must be rapid, judging from the rapid- 
ity of the inward and outward flow of water from the oral cavity. 
It would seem that selection is governed more by the size of 
particles taken into the oral opening than by the quality. 
THE RELATION BETWEEN THE MEGANUCLEUS AND THE 
MICRONUCLEUS 
This relation presents one of the most interesting features for 
future work with this species. It is unfortunate that out of 
many hundreds of individuals studied not one has been seen in 
division, and no conjugating pairs have been found. 
The enclosure of the micronucleus within the meganucleus is 
too regular in its occurrence to be accidental, or without signif- 
icance of some kind. Two possibilities suggest themselves : 
Either it represents a type of nuclear division of a rather new 
and remarkable kind, or it represents a process of nuclear re- 
organization perhaps along the line of endomixis. Unfortu- 
nately the picture so far presented is too incomplete to admit 
of definite conclusions regarding either supposition. There is 
also the added handicap of incomplete knowledge of division 
phases of the micronucleus. 
