PLATE LI I 



PAGE 



Figs. 1, 2. CORYNOIDES cALicuLARis Nicholson , 206 



Nicholson's figures of this small, interesting graptolite. 

 Middle Ordovician of Great Britain. 



Pigs. 3, 4. CLIMACOGRAPTUS SPINIFER (Ruedemann) 203 



Two rhabdosomes. 



Ordovician (Cincinnatian), Utica shale of eastern New York. 



Figs. 5-7. CLIMACOGRAPTUS PUTILLUS (Hall) 202 



Three examples enlarged showing the characteristics of the species. 

 Ordovician (Cincinnatian), Utica shale of New York. 



Figs. 8, 9. SCHIZOCRANIA FILOSA (Hall) 235 



8. Valve of Rafinesquina alternate/, with five pedicle valves of this 



species attached. One specimen shows the scars of the brachial 

 valve. 



9. Exterior of a brachial valve attached to Rafinesquina. X 2. 



Ordovician (Cincinnatian), Maysville group, Cincinnati, Ohio. 



Figs. 10-12. CYCLORA MINUTA Hall 316 



Three views of this dwarfed gastropod. X 6. 



Ordovician (Cincinnatian), Maysville group, Cincinnati, Ohio. 



Fig. 13. LEPTOBOLUS INSIGNIS Hall Z31 



Exterior of the shell showing the concentric and radiating striae. 

 X8. 



Ordovician (Cincinnatian), Utica shale, Middleville, New 

 York. 



Figs. 14-16. BYTHOCYPRIS CYLINDRICA (Hall) 371 



Side and two edge views of a complete carapace. X 20. 



Ordovician (Cincinnatian), Eden shale, Cincinnati, Ohio. 



Fig. 17. CRYPTOLITHUS TESSELLATUS Green 335 



Diagrammatic drawing of an entire specimen. 

 Upper Ordovician of Canada. 



Figs. 18-20. TRIARTHRUS BECKI Green 342 



Outline drawings of three specimens. 



Ordovician (Cincinnatian), Utica shale, New York. 



Figs. 21-23. CARYOCARIS SILICULA Bassler n. sp 372 



21. Valve of this crustacean, imperfect at one end. X 3. 



22. A less complete example. X 3. 



23. A specimen representing the opposite valve. X 3. 



Ordovician (Mohawkian), lower beds of Martinsburg shale, 

 Strasburg, Virginia. 



Figs. 24, 25. LEPIDOCOLEUS JAMESI (Hall and Whitfield) 371 



Detached plates, enlarged. 



Ordovician (Cincinnatian), Eden shale, Cincinnati, Ohio. 

 Figs. 1, 2 are after Nicholson; 3-7 after Ruedemann; 8, 9, 24, 

 25 after Hall and Whitfield; 14-16 after Ulrich; and 13 after Hall 

 and Clarke. 



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