NOTES ON SOME CANADIAN INFUSORIA. 307 
versely wrinkled on the concave border. These points, however, do 
not appear to be of sufficient moment to authorize the establishment 
of a new species. 
A peculiar feature in the ingestion of food was noticeable, which 
1 have observed in no other form. Below the termination of the 
pharynx was a clear spot (v), which appeared to be ciliated on first 
looking at it, but the ciliation on further examination was seen to 
belong to certain structures contained therein. On watching it, it 
was seen to detach itself after a time from the pharynx and pass 
down the left side of the body close underneath the cuticle, the cilia 
continuing to work until it reached that point where the body com- 
mences to taper off into the foot, where it stopped and gradually disap- 
peared. In the meantime a new spot has appeared at the termination 
of the pharynx, and it in its turn passes through the same changes. 
I believe the explanation of this phenomenon is to be found in the 
manner of feeding. The clear spot is merely an enormous food 
vacuole, the animal not absorbing its food into the protoplasm of the 
body, until a considerable quantity of it has been collected, and the 
apparent ciliation of the vacuole, as stated above, is due to the pres- 
ence of ciliated forms in its interior. The appearance and disap- 
pearance of the vacuole is apparently rhythmical, but this was due to 
the animalcule being in a situation to obtain a large and constant 
supply of nutrition, but even then the intervals between the swallow- 
ing of the vacuoles varied considerably. 
CyYcLIDIUM GLAUCOMA, EHERH AND MARGARITACEUM. 
These two forms occurred in considerable abundance, particularly 
the former, which, however, seemed to be rather susceptible to cold, 
while the latter was not affected. C. glaucoma (fig. 3) measures 
about 0.019 mm., and is covered throughout with bristle-like cilia, 
which, however, are capable of very powerful action. At the 
posterior extremity of the body (and not the anterior as has been 
stated) is the contractile vesicle (c.v.), and behind it an extremely 
long seta. The mouth is situated on the under surface of tke body, 
and is provided with an exceedingly large hood-shaped retractile 
structure (2). These forms collect in large numbers wherever the 
light shines most strongly. Their motion is exceedingly rapid and 
jerky ; usually remaining at rest, when disturbed one after the 
22 
