PRIMARY INHIBITION OF CILIARY MOVEMENT 419 
In some experiments on Beroé, using cocaine (0.1 to 0.5 per 
cent cocain chloride), effects were observed resembling in 
many respects those caused by atropin. It is accordingly prob- 
able that cocaine also paralyzes the primary inhibitory appara- 
tus of the swimming rows. In addition it strongly stimulates 
the smooth musculature. On account of scarcity of material of 
the animals it was impossible, however, to arrange as many 
experiments with cocaine as would have been desirable. In an 
experiment with chloroform (0.5 per cent) this turned out at 
first to stimulate both the primary and the secondary inhibitory 
apparatus of the swimming rows. After about 20 minutes’ effect 
both the musculature and the ciliary rows were totally para- 
lyzed, but the animal was still clearly transparent. On being 
returned to the aquarium it recovered, at least partly. The 
effect of chloroform resembled, although not in all details, that 
of ethyl ether. 
A number of experiments in which specimens of Beroé were 
subjected to the effects of curarine, stovaine, and amylenhydrate 
did not appear to give any direct information as to the inhibitory 
mechanism of the rows of swimming plates and are accordingly 
left out of consideration here. Curarine in a concentration of 
1:10,000 did not paralyze the swimming plates or their primary 
inhibitory apparatus, but stimulated the smooth musculature of 
the animal. 
9. Experiments on isolated swimming plates of Beroé. The 
preparations for these experiments were obtained by shaking 
specimens of the animal in a test-tube with a slight amount of 
sea-water, so that the meridional rows were mechanically broken 
up into separate swimming plates. For reasons of economy, I 
selected for these experiments such animals as had suffered some 
minor injury when being caught. Two quite uninjured, though 
small, individuals, however, were treated in the same way: these 
had shown a rapid motion in the aquarium before they were 
shaken to fragments. But in the shaken preparations of these 
animals there was not found a single spontaneously active 
swimming plate. It must, however, be added that the prepa- 
ration in question was not watched for longer than about an hour. 
