404 WM. A. KEPNER AND W. CARL WHITLOCK 
about it, but not touching it, about as Blochmann ('94) and 
Mast and Root ('16) indicate to be the usual method of ingesting 
Paramecium. The latter authors saw some very interesting 
exceptions to this method of swallowing Paramecium. We, too, 
have observed departures from this type of reaction. On May 
2, 1919, we had a hanging drop in which there had been many 
Colpidia, but which were now dying off. ' The dead ones, though 
frequently encountered by the ameba, were not in any case 
ingested. The living Colpidia were frequently accepted in wide 
embraces. The paramecia in this hanging drop were peculiar 
in that they were wider than normal ones and rather sluggish. 
Then, too, their bodies were so phable that an ameba's pseudo- 
pod, advancing against the dorsal side of one of them, would 
indent it. Moreover, when the paramecia were crowded between 
two amebas, they became greatly flattened and even in some 
instances bent upon themselves at right angles. The cilia and 
contractile vacuoles of these peculiar paramecia were active. 
The amebas attacked these relatively inactive paramecia over 
and over; but in each instance their attack was peculiar in that 
they attempted to surround these ciliates closely or intimately. 
Because of this unusual method of attempting to capture the 
paramecia they caught none, for after two-thirds or less of the 
length of the Paramecium's body had become involved in the 
embrace of the ameba, the Paramecium would slowly glide out 
and remain by the side of the ameba until it would again be 
partially enclosed in a second embrace, when it would move out 
■of the enclosing arms of its would-be captor. The conduct of 
the amebas toward these unusual paramecia is itself peculiar 
and exceptional. Here for some reason the ciliary disturbance 
of the water by the paramecia has not resulted in stimulating 
the amebas in such manner that they sent out about the prey 
remote encircling pseudopods. 
A further departure from the usual method of ameba in cap- 
turing Paramecium was observed March 19, 1919. This ameba 
was first seen at 10 :10 a.m. It was then perfectly quiet, spending 
all of its available energy upon the partly constricted Para- 
mecium. The ameba showed no cytoplasmic movement (fig. 
