16 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 74 



and narrow coliimnals. It is perforated by a small obscurely 

 pentalobate canal. 



Genotype, — Cyathocrmus Tiexodactylus Lyon and Casseday 

 {Cyathocrinus lyoni Hall). 



Geological range. — The typical forms of the genus occur in the 

 lower Carboniferous (Mississippian), but undescribed species from 

 the high Middle Devonian have been examined that may be referable 

 to the genus. 



EXPLANATION OF PLATES 



Plate 1 



The figures within the clotted frame (fig. 10) are photographic copies of 

 Lyon's original illustrations. The numbers 3-3e are the same as Lyon's original 

 numbers. 



Vasocrinus sculptus Lyon 



F^G. 1. Posterior view of holotype. 



Fig. 2. Basal view of holotype. 



Fig. 3. Enlargement X 3 of portion of dorsal cup showing detail of weathered 



plate folds. 

 Fig. 10 (3c, Sd, 3e). Lyon's original figures of the holotype. 

 Middle Devonian, Sellersburg limestone (of Hamilton age). Falls of the Ohio, 

 Louisville, Ky. 



Vasocrinus valens Lyon 



Figs. 4, 5, 6. Basal, posterior, and left anterior views of specimen referred by 



Lyon to V. sculptus, but here considered as a cotype of V. valens. 

 Fig. 10 (36). Lyon's figure of the same specimen. 

 Figs. 7, 8, 9. Lateral, basal, and ventral view of Lyon's type of V. valens, 



showing the imperfect cup. 

 Fig. 10 (3«). Lyon's original figure of this specimen. 

 Fig. 10(3). Lyon's generic diagram cited as V. valens, evidently a composite 



of his figures 3a and 3&. 

 Middle Devonian, Jeffersonville limestone (of Onondaga age), quarries on 



Beargrass Creek, near Louisville, Ky. 



Plate 2 



Vasocrinus turbinattis, new species 



Figs. 1, 2, 3. Posterior, tegminal, and anterior views of the holotype. 

 Fig. 4. Diagram of this specimen, which serves as a generic diagram for 

 Vasocrinus. 

 Middle Devonian, Jeffersonville limestone (of Onondaga age), Louisville, Ky. 



Vasocrinus sculptus Lyon 



Fig. 5. Left anterior viewX2 of a small specimen showing the madreporite and 

 two primibrachs with their covering plates. The horizontally disposed 

 structure back of the ai'm base and to the right is the ventrsfl sac. 



Fig. 6. Basal view of large specimen showing two primibrachs in one ray. 



Figs. 7, 8, 9, 10. Posterior, tegminal, left posterior interradial and basal views 

 of another sjiecimen. 

 Middle Devonian, Sellersburg limestone (Hamilton), Falls of the Ohio, 

 Louisville, Ky. 



o 



i 



