150 
SYDNEY J. HICKSON AND .1. T. WADSWORTH, 
round on its axis. But all the time particles of its protoplasm 
can he seen streaming down the suckers of the Dendrosoma 
into the arm. The Dendrosoma never seems to use the whole 
bunch of suckers at the end of an arm for feeding at the 
same time. From one to six or seven, according to the size 
and strength of the prey, may be used, the others being 
stretched out unconcerned with what is going on in their 
neighbourhood as if in search of other victims (fig. 30). 
The usual statement made in the text-books is that the 
Acinetaria paralyse their prey before feeding on them, and 
this is used as an argument that a fluid of some kind passes 
down the tentacle towards the food before the return current 
of the food substance sets in. We are cjuite certain that in 
Dendrocometes such a paralysis of the food animals does take 
})lace. We have seen on several occasions small Paramecia 
caught and paralysed by the arms of this remarkable form. 
Biitschli (2) gives several examples of the pai-alysing pro- 
})erties of the Acinetarian suckers, and quotes cases observed 
by 8tein in j\I etac i neta., Maupas in Sphmrophrya, Plate 
in Hypocoma. 
Claparede and Lachmann (vol. ii, p. 50), however, record 
that a Stylonychia caught by “an Acinetau ” struggled for a 
long time and then underwent fission. One of the daughter 
individuals escaped from the Acinetau, leaving her sister to 
be devoured. 
Levick (23) also does not mention that the Infusoria upon 
which Dendrosoma feeds are paralysed, but says that the 
tentacles are capable of “ resisting the struggles of the 
captive.” 
Since we made our first observations on the feeding of 
Dendrosoma we have occasionally found a smaller infusorian 
caught by the tentacles, but time after time we have failed 
to induce them to feed upon the common Paramecium 
a u roll a from our cultures. 
But although we have succeeded in inducing the Dendro- 
soma to feed we have failed to keep them alive in the labora- 
tory for more than a few days. The material soon becomes 
