PLATE LXXV. 



Page 



Camptocrinus myelodactylus W. and Sp 779 



Fig. 1. A specimen with stem and cirri. (Coll. W. and Sp.) 



2a and b. Portions of the coiled stem in different specimens, showing the cirri. 



Dichocrinus Blairi S. A. Miller 778 



3. The type specimen. (After Miller.) 



Dichoceinxts HuiTTSviLLJB W. and Sp 773 



4. The type specimen. fColl. W. and Sp.) 



Dichoceinus cnsreTUS S. A. Miller 764 



5. Specimen with arms. (Same collection.) 



Dichocrijstus conus Meek and Worthen 770 



6. The type specimen. (Illinois State collection.) 



Platycrinus canaliculatus Hall 689 



la. Specimen with arms. (Coll. W. and Sp.) 



lb. Dorsal aspect of the calyx. (Same collection.) 



Platycrikus sculptus Hall 691 



8. A large specimen with arms. (Same collection.) 



9. A smaller specimen. (Mus. Comp. Zool.) 



Platycrinus americanus 0. and Sh 686 



10. A mature specimen with arms; the latter biserial from above the last bifur- 



cation. (Coll. W. and Sp.) 



11. A young specimen ; the arms uniserial and zigzag, the joints elongate, and 



the pinnules far apart. (Same collection.) 



12. Dorsal aspect of the calyx. (Same collection.) 



13a. Side view of the calyx of a large specimen. (Same collection.) 

 135. Anal side of the same specimen. 

 13c. Ventral aspect of the same. 



14. Natural cast, probably of Culicocrlnus 735 



Prom the Niagara group of Iowa. (Same collection.) 



