Encrinaster yachalensis nov. 

 Page 117 



1 Holotype. Natural size. 



2 Basal part of abactinal view of ray and portion of disk, enlarge* 



x 5, showing the ambulacral ossicles and impressions of th< 

 adambulacrals and the numerous accessory marginal plate: 

 of the disk. 



3 Portion of ray near tip, exhibiting only the ambulacral ossicle; 



in abactinal view, x 5. 



4 Portion of oral armature, showing the simple, curved jaw; 



carrying long, slender syngnaths. , x 5. 



5 Enlargement (x 5) of a small portion of a ray retaining th< 



adambulacrals on right side of figure. 

 Silurian of Quebrada del Aguadido, Cerro Blanco, Yachal ii 

 Argentine Republic. 



Argentinaster bodenbenderi nov. 

 Page 118 



6 Holotype. Natural size. 



7 Diagrammatic restoration of abactinal view of base of ray anc 



oral armature, x 5. 

 Silurian of Quebrada del Aguadido, Cerro Blanco, Yachal ii 



Argentine Republic. 

 The two holotypes are in the New York State Museum. 



184 



