NOTES ON CYCLOCYSTOIDES 
27 
This is the specimen which retains a portion of plated tube 
which Salter and Billings thought might be connected with the ^ 
Cyclocystoides. From its position it would be easy to argue that ‘ 
it did, but no connexion can actually be seen (the tube probably 
runs under the Cyclocystoides ) , and the economy of the animal 
does not demand such a tube. * 
A second good specimen, referred to this species, was collected 
by Mr. W. A. Johnston from the crinoid beds at Kirkfield, Ont. 
This specimen is oval in outline, 11 mm. in greater and 8| mm. 
in lesser diameter, and has 30 plates in the sub-marginal ring. 
The disk, except for a small fractured portion, is covered with 
small close-fitting plates, which cover the whole surface and are 
not full of pores as on the lower side. There does not appear to 
be any opening on this surface of the disk, except where plates 
are accidentally missing. The disk is marked by bifurcating 
ridges which radiate from the centre. Upon analysis, it is seen 
that there are one or two ridges in front of each of the sub- 
marginal plates, and that each two adjacent ridges quickly unite 
to form a single ridge. Two of the ridges thus formed unite 
Fig. 2. Diagram of Cyclocystoides . 
Collected by W. A. Johnston. 
a little nearer the centre and are joined quite close to the centre 
by another long ridge formed from four shorter ones. Thus, 
there are five main ridges, each of which is subdivided so that it 
sends branches to six plates. This is shown in the accompany- 
ing camera-lucida drawing (fig. 2). These ridges probably cover 
ducts which lead from the plate to the centre, and the inference 
might be that through them, food, in water, was carried from 
