PLATE VI. 



Pentacrinus tehamaensis Clark, n. sp. (p. 35). 



U. S. Nat. Mus. 31194, type. 



Figure 1. Articular surface of a detached joint of the column, X 2. 



Pentacrintts bryani Gabb (p. 35). 



Acad. Nat. Sci. Philadelphia 1458, type. 



Figure 2a. Lateral view of a portion of a joint column. 

 2b. Articular surface of the column. 



Uintacrintjs socialis Grirmell (p. 36). 



Mus. Comp. Zoology, Cambridge. (Figures after Springer.) 



Figure 3a. Monocyclic; regular; centrale of maximum size. 

 3b. Monocyclic; irregular; double centrale. 

 3c. Dicyclic; irregular; double centrale and 1 IB. 

 3d. Dicyclic; regular; IBB fully developed. 

 3e. Specimen, with three individuals, showing dicyclic and monocyclic forms of base, and maximum and 



small size, lying together in close contact on the slab; the black membrane lining the calyx is also shown 



at the edge of the broken plates. 

 3f. Uintacrinus westfalicus Schlueter. Figure of the type specimen for comparison (after Schlueter). 

 3g. Specimen laterally compressed ; showing the fixed and proximal free pinnules, and the anal tube in natural 



position. 

 3h. Articulating surfaces of brachials, enlarged X 2.2; to show the diagonal direction of the fulcral ridges. 



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