NOTES ON OYCLOCYSTOIDES 
31 
derm is known in which the food groove is not radial, instead of 
circular, and does not lead directly to the mouth. In the second , 
place, there does not seem to be any aperture for the discharge 
of the great amount of water which would be drawn into the 
body, for, were it discharged through the anal opening, there 
would be no opportunity for digestion. It is possible that a 
more complete specimen than has yet been found would explain 
this objection, so that it has not as much weight as the first one. 
A second interpretation is, however, possible. The organism 
may be the highly specialized root of a free crinoid. At the 
centre of the disk of the specimen from Kirkfield, there is just 
the suggestion of a scar, as if a small stem might have been 
attached. There are many crinoid roots which show a method 
of bifurcation somewhat similar to the ridges shown on this and 
other specimens, and Licheriocrinus , at least, shows a root which 
is plated and which further has radial canals beneath the surface. 
Interpreted thus, Cyclocystoides would have been a sort of 
sucker-disk which, being flexible on the lower side, and having 
a flexible apron around it, could, by the expulsion and ingestion 
of water, make a partial vacuum, and thus attach or loosen 
itself at will. The so-called anal opening would then become 
an orifice for the expulsion of water. It is even possible, if one 
is sufficiently imaginative, to think of this disk as a swimming 
organ, the method of propulsion being on the same principle as 
in some of the cephalopods. 
Bibliography. 
Bather, F. A. Treatise on Zoology. Edited by E. Ray 
Lankester. Echinodermata, p. 210, fig. VIII, 1900. 
Billings, E., and Salter, J. W. Canadian Organic Remains, 
Decade III, p. 86, 1858. 
Billings, E. Palaeozoic Fossils of Canada, Vol. I, p. 393, fig. 369. 
Faber, C. L. Journal Cincinnati Society of Natural History, 
Vol. IX, 1886, p, 17, PL I, fig. 1. 
Hall, James. Foster and Whitney’s Report on the Lake 
Superior Land District, 1852, p. 209, PL XXV, fig. 4 a-c. 
Hall, James. 24th Report New York State Museum Natural 
History, 1866, p. 218, PL VI, fig. 16. 
