NO. 1850. KN0BST0^'1<! CRICOID FAUNA— SPRlyGER. 201 



Locality. — Several good specimens were found at Whites Creek, 

 and at Newmarket, Kentucky; the latter from the Knobstone shales, 

 the former among intermingled fossOs, some reddish and some bluish- 

 gray, from both Keokuk and Knobstone, with the probability that 

 most of them came from the latter. 



4. Another closely related, rather small form is that of B. quin- 

 quelohus Meek and Worthen, described from the Warsaw Group of 

 Illinois and found at several localities of the typical Keokuk. With 

 onl}^ moderate and often no projections on the radials, the center of 

 the basals is abruptly elevated to a small point; from this a strong 

 ridge, widening and tending to form a shallow grooved depression 

 between the margins, runs to the infrabasals, giving the distinct form 

 of a large, five-pointed star involving the whole basal portion of the 

 calyx. The name "stellatus'' would have been absolutely appropriate 

 for this. This, form of base is best defined in the Keokuk forms, but 

 may be traced from the Lower Burlington, where it is found in 

 B. rJiombiferus. 



Locality. — Good specimens of this are found in the Knobstone 

 shales at Newmarket, Kentucky, and at Wliites Creek in a red pres- 

 ervation of uncertain horizon. I have also very characteristic speci- 

 mens of it from the top of the Keokuk or Warsaw near Colesburg, 

 Hardin County, Kentucky. 



5. Another small form, with very small, tumid BB, and extremely 

 large, convex RR, with large, deep facets facing laterally, is somewhat 

 like B. tumidus Hall, from the Iowa Keokuk. From the deep radial 

 facets, and the appearance of some arm fragments that may belong 

 to it, it is possible that this and the next form may belong to Cyatho- 

 crinus. Their low calyx and flat base, unusual in that genus, and 

 the extreme size of the facets, occupying almost the entire plate, lead 

 me to place it here ; but it has an erectness, and absence of spreading 

 in the cah^x, which are unlike Barycrinus. Only the definite asso- 

 ciation of arms can settle it. 



Locality. — There are good specimens from Button-mould Knob — 

 one complete calyx— and several from Wliites Creek, in both reddish 

 and bluish preservation, but none found in place. 



6. In the last four species the surface is smooth and without orna- 

 ment. There is another form, in shape and size closely resembling 

 the last, and possibly a Cyatliocrinus, in which the plates, in addition 

 to being tumid, are surrounded by a number of more or less promi- 

 nent, small nodes, sometimes tending to arrange themselves in rows 

 from center to center; they fringe the margins of the radial plates 

 like rows of beads, and also the brachials (of which three are in place 

 in a ray of one specimen) all the way around to the ventral furrow. 



