PLATE LXXV. 



Pack 



Camptocrinus myki.odactylus W. and Sp 77'J 



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



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



DicHOCRixus Blairi S. a. Miller 778 



3. The type specimen. (After Miller.) 



DicHOCEiNus HUNTSviLL.-E W. and Sp 77.'' 



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



DlCIIOCRINL'S CIXCTUS S. A. MiLLER 7G1 



5. Specimen with arms. (Same collection.) 



DiCHOCRiNUS coxus Meek and Worthen 770 



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



Platycrinus canaliculatus Hall 689 



7a. Specimen with arms. (Coll. W. and Sp.) 



~b. Dorsal aspect of the calyx. (Same collection.) 



Platycrixus sculptus Hall 691 



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



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



Platyckints americaxus 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.) 



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

 \?>h. Anal side of the same specimen, 

 l.'v-. Ventral aspect of the same. 



11. Natural cast, probably of Culicocrincs 735 



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



