PLATE LXIX. 



Page 

 Platyceinus symmetbicus W. and Sp 655 



Pig. la. Specimen with arms and column. 



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



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



Platyceinus planus 0. and Sh 668 



2a. 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.) 

 3b. 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. 



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

 lateral interradius at the top.) 

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

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

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



Platyceinus Agassizi W. and Sp 669 



4. A very large specimen with arms. 



Platyceinus pileifoemis Hall 656 



5. A specimen with arms (slightly restored). 



Platyceinus boncensis White 683 



6. A specimen having six arms to the ray. 



Platyceinus SAEiE Hall 677 



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



(All specimens in the collection of Wachsmuth and Springer, except that of 3a, 

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

 Illinois State Museum.) 



