PLATE LXIX. 



Page 

 Platyceinus symmetricus W. and Sp 655 



Fig. In. Specimen with arms and column. 



lb. Ventral aspect of the calyx ; a large specimen. 



Ic. Ventral aspect of a young specimen ; the orals almost symmetrical. 



Platyceinus planus O. and Sh 668 



2((. A large specimen with arms. 



2b. Lateral view of the dorsal cup. 



2c. A portion of the arms enlarged. 



2d. A young specimen, apparently of this species. 



Platyceinus buelingtonensis 0. and Sh 653 



3a. A medium sized specimen with arms. (After Meek and Worthen.) 



'Sb. Lateral view of a large calyx. 



3c. Ventral aspect of another large specimen, showing the anal tube. 



3d. Posterior view of a smaller specimen. 



3e. Ventral aspect of another small specimen. 



3/. Dorsal cup of a young specimen. (Inadvertently drawn with left antero- 

 lateral interradius at the top.) 



3'j. A very young specimen with zigzag arms, composed of single joints. 



3//. Portion of an arm showing the lateral processes (enlarged). 



3!'. Portion of an arm in a dorsal aspect (enlarged). 



Platyceinus Agassizi W. and Sp 6G9 



4. A very large specimen with arms. 



Platyceinus pileifoemis Hall 656 



5. A specimen with arms (slightly restored). 



Platyceinus boncexsis White 683 



6. A specimen having six arms to the ray. 



Platyceinus sae.^ Hall 677 



7. The type specimen. (After Hall.) Somewhat flattened. 



(All specimens in the collection of Wachsmnth and SjDringer, except that of 3ff, 

 ■which is in the Museum of Comparative Zoology, and Fig. 7, which is in the 

 Illinois State Museum.) 



