PLATE I. 



Isocrinus smithi Clark, n. sp. (p. 21). 



U. S. Nat. Mus. 31184, type. 



Figure la. Articular surface of a detached joint of the column, X 4. 

 lb. Lateral view of a detached joint of the column, X 4. 



Isocrinus californicus Clark, n. sp. (p. 21). 



U. S. Nat. Mus. 31185, type. 



Figure 2a. Articular surface of a detached joint of the column, X 6. 

 2b. Lateral view of a portion of the column, X 6. 

 2c. Several specimens of column joints. 



Encrinus hyatti Clark, n. sp. (p. 22). 



U. S. Nat. Mus. 31186, type. 



Figure 3a. Articular surface of a detached joint of the column, X If. 

 3b. Lateral view of a portion of the column, X If. 



Aspidura (?) iDAHOENSis Clark, n. sp. (p. 23). 



U. S. Nat. Mus. 31187, type. 

 Figure 4. Cast of two specimens. 



Cidaris shastensis Clark, n. sp. (p. 23). 



U. S. Nat. Mus. 31188, type. 



Figure 5. Fragment of interambulacral plate, X 3. 



Cidakis dilleri Clark, n. sp. (p. 23). 



U. S. Nat. Mus. 31189, type. 

 Figure 6. Portion of test. 

 230 



