300 BULLETIN 88, UNITED STATES NATIONAL MUSEUM. 



FIG. 4. Tetraster wyville-thoTtisoni Nicholson and Etheridge. 



Diagram X 4 of the actinal skeleton. From a wax squeeze by Bather, 

 in the United States National Museum (Cat. No. 60614). 



Upper Ordovicic. Thraive, Girvan, Scotland. 

 FIG. 5. Schcenaster (?) montanus Raymond. 



Reproduction X 2 of the original figure. Actinal side. 

 Mississippi (Madison). Spring Canyon, near Alder, Montana. 

 Collection of the Carnegie Museum. 

 FIG. 6. SJicenaster (?) wachsmuihi Meek and Worthen. 



Reproduction, natural size, of the original figure. Actinal view. 

 Lower Mississippi (Burlington). Burlington, Iowa. 

 Collection of the Museum of Comparative Zoology, Harvard University 

 (No. 7). 



PLATE 34. 



FIG. 1. Palseosolaster (?) gyalum (Clarke). 



Actinal view of one of the cotypes, natural size. 

 Upper Devonic (Portage). Ithaca, New York. 

 Collection of Cornell University. 



PLATE 35. 



FIGS. 1-4. Schcenaster fimbriatus Meek and Worthen. 



1. View of the abactinal side, natural size, of one of the cotypes. 



2. Enlarged view of one of the rays, showing the arrangement of the 

 ossicles and the pores, as seen when the surface is ground down. 



3. Actinal side of a ray, enlarged, showing only the adambulacrals. 



4. Actinal side of another cotype, natural size. 

 The original figures of plate 19, figs. 7 a to 7d. 



Upper Mississippi (St. Louis). St. Clair County, Illinois. 

 FIGS. 5 and 6 Encrinaster petaloides (Simonovitsch). 



5. Abactinal view, about X 2. 



6. An arm from the actinal side, about X 2. 

 After Schondorf. 



Lower Devonic (Upper Coblenzian). Niederlahnstein, Germany. 



PLATE 36. 



FIG. 1. Tseniaster spinosus (Billings). 



Photograph X 2 showing the actinal side of one of the cotypes. 

 Middle Ordovicic (Lower Trenton). Montmorency Falls, Quebec, 

 Canada. 



Collection of the Geological Survey of Canada (No. 1404). 

 FIGS. 2 and 3.Taeniaster cylindricus (Billings). 



2. Abactinal view X 2 of one of the cotypes. 



3. Actinal view X 2 of another cotype. Both specimens are on the 

 same slab. 



Middle Ordovicic (Trenton). Ottawa, Canada. 

 Collection of the Geological Survey of Canada (No. 1405a). 

 FIG. 4. Alepidaster flexuosus (Miller and Dyer). 



An unpublished photograph X 3.5, made many years ago, of the holo- 

 type of Protasterina fimbriata Ulrich. 



Upper Ordovicic (Lower Edenian). Covington, Kentucky. 

 Ulrich collection of the United States National Museum (Cat. No. 60615). 



