PLATE LXXVII. 



Page 

 Dichocrinus polydactylus Cass, and Lyon ........ 756 



la. A large specimen with arms. 



lb. Posterior view of calyx, showing the elevated dome and disk ambulacra. 



Dichocrinus lachrymosus Hall . 754 



2a. Specimen with arms and stem. 

 2b. Posterior view of calyx. 

 2c. Ventral aspect of same. 



Dichocrinus liratus Hall 759 



3a. Specimen showing the arms and stem. 

 3b. Posterior view of the dorsal cup. 



Dichocrinus cinctus Miller and Gurley 764 



4a. Posterior view of specimen with arms. 

 4b. Ventral aspect of the calyx. 

 4c. Distal face of first distichal (f ). 



Dichocrinus plicatus Hall 758 



5a. A small specimen with arms and stem. 



5b. Another specimen, giving a side view of the dorsal cup. 



Dichocrinus ornatus "W. and Sp 762 



6. Specimen with arms and stem, from near Mt. Pleasant, Iowa. 



Dichocrinus i,jevis Hall 7(55 



la. Specimen with arms. (Coll. Mr. Pultz of Burlington.) 



lb. Another specimen. (Same collection.) 



7c. Portion of an arm with pinnules (enlarged). 



Dichocrinus ovatus 0. and Sh „ 7(30 



8a. A specimen with arms. 



8b. Posterior view of the dorsal cup. 



Dichocrinus oblongus W. and Sp 759 



9. Posterior view of the type specimen. 



