54 CANADIAN FOSSILS. 



Cleiocrinus grandis, Billings. 

 Plate V. Figures 2a-2c. 



Description. — The column of this species is large, obscurely pen- 

 tagonal, and composed of thin joints, every alternate one of which 

 is about one fourth of a line wider than the one on each side of it. 

 In consequence of this inequality in the size of the joints the column 

 is closely annulated with slightly projecting rings, from six to eight 

 in three lines. When perfect it is rounded-pentagonal, but when 

 crushed it divides into five longitudinal lobes, as represented in 

 figure 2b. Each joint appears to be composed of five pieces, and 

 the articulating surfaces are striated with numerous fine, curved, 

 radiating ridges. The radix or base of attachment of the column 

 consists of a number of large roots, which appear to be composed of 

 small polygonal plates. The alimentary canal is very large and 

 nearly circular. 



These columns have so nearly the structure of those of C. regius^ 

 that I have no doubt they belong to a species of that genus. 



Explanation of Figpkes. Plate V. 



Figure 2a. Portions of two individuals of this species, which appear to have 

 grown upon the same spot. 

 " 2b. Fragment of a column, crushed. 

 " 2c. Transverse section, shewing the large alimentary canal. 



Locality andformatioru — Trenton limestone, Ottawa. 



Cleiocrinus magnificus, Billings. 



Plate V. Figure 3. 



Description. — In this species the column is nearly round and 

 composed of thin joints, of which there are from six to eight in two 

 lines. The alimentary canal is pentagonal, and six lines in diameter 

 where the column is nine lines. The cup has never been seen, but 

 the size and form of the fragments of the stalk are suflicient to 

 distinguish this species from any other in the Trenton limestone. 

 It appears to belong to the genus Cleiocrinus. Diameter of column, 

 from nine lines to one inch. 



Locality and formation. — Trenton limestone. City of Ottawa. 



