REVISION OF PALEOZOIC STELLEEOIDEA. 295 



Figs. 4 and 5. — Promopalxasler bellulus, new species (also see plates 15 and 16). 



4. Adambulacralia and their spines, X 7. The ambulacrum lies to 

 the left. 



5. A few abactinal spines, X 7. 



Upper Ordovicic (Richmondian). Waynesville, Ohio. 



Harris collection of the United States National Museum (Cat. No. 

 40879). 

 Fig. G. — Promopalseaster icyJcoffi (Miller and Gurley) (also see plate 19). 



Diagram X 3.5 of one of the interbrachial areas. 



From the holotype. 



Upper Ordovicic (Richmondian). Near Madison, Indiana. 



Collection of the University of Chicago (No. 6066). 

 Fig. 7. — Promopalseaster exculplus (Miller) (also see plate 20). 



Adambulacral and ambulacral plates at about mid-length of a ray, X 4. 



From the holotype. 



Upper Ordovicic (Richmondian). Near Waynes\dlle, Ohio. 



Harris collection of the United States National Museum (Cat. No. 

 60608). 

 Fig. 8. — Promopalseaster dyeri (Meek) (also see plates 20 and 25). 



Five inframarginal plates X 4. To show the articulations for the stout 

 spines that lie on the right. Also note the smaller spines. The plate 

 extensions to the left connect with the vertical ridges on the ambulacral 

 plates. 



From the holotype. 



Upper Ordovicic (Maysvillian). Cincinnati, Ohio. 



Dyer collection of the Museum of Comparative Zoology, Harvard Univer- 

 sity (No. 13). 



Plate 19. 



Fig. 1. — Trimeraster parvulus Schondorf. 



Reconstruction X 1.75 of the actinal side. After Schondorf. 



Lower Devonic (Coblenzian). Near Rhens, Germany. 

 Fig. 2. — Promopalseaster leykoffi (Miller and Gurley) (also see plate 18). 



Photograph X 2 of the holotype, showing the actinal side. One of 

 the finest of Paleozoic specimens. 



Upper Ordovicic (Richmondian). Near Madison, Indiana. 



Collection of the University of Chicago (No. 6066). 



Plate 20. 



Fig. 1. — Anorthaster miamiensis (Miller) (also see plate 13). 



Camera lucida drawing X 5.5 of one of the interbrachial areas of the 

 holotype. The only Paleozoic form known with the area wholly made 

 up of adambulacrals. 



Upper Ordov-icic (Richmondian). Waynesville, Ohio. 



Harris collection of the United States National Museum (Cat. No. 

 40880). 

 Fig. 2. — Promopalseaster exculptus (Miller) (also see plate 18). 



Camera lucida drawing X 4 of an interbrachial area. Note the modified 

 ambulacral plates in connection with the oral armature. Holotype. 



Upper Ordovicic (Richmondian). Near Waynesville, Ohio. 



Harris collection of the United States National Museum (Cat. No. 

 60608). 



