PAGECRINUS, A NEW CRINOID GENUS FROM THE 

 AMERICAN DEVONIAN 



By Edwin Kirk, 



0/ the United States Geological Survey 



Among the iinworked and unstudied material of the Springer col- 

 lection in the United States National Museum a tray of crinoids was 

 found representing a new and interesting genus. The material was 

 apparently acquired by purchase, but from what collection it came 

 can not be determined. The original locality label bears the legend 

 " Niagara group, St. Paul, Ind." A label in Mr. Springer's handwrit- 

 ing gives the horizon as "Onondaga Gr." and the locality as "Near 

 St. Paul, Ind." This change in horizon was probably based on 

 information acquired subsequent to the purchase while Mr. Springer 

 was making an intensive study of the Silurian crinoids. The Onon- 

 daga age of the material is further assured through the determination 

 of a number of well-preserved Bryozoa associated with the crinoids 

 by Dr. R, S. Bassler. 



PAGECRINUS, new genus 



The genus is represented by a single known species, Pagecrinus 

 gracilis, new species, and of necessity the generic diagnosis is drawn 

 up from information furnished by this form. 



Pagecrinus is a dicyclic inadunate crinoid, the afHnities of which 

 seem closest with the family group Botryocrinidae as defined by 

 Bather. The relatively huge basals, the structure of the posterior 

 interradius and ventral sac, and the arm structure are strikingly like 

 the Carboniferous genus Belemnocrinus . Belemnocrinus is generally 

 considered a monocyclic genus, but it may eventually prove a pseudo- 

 monocyclic form derived from just such a Devonian ancestor as 

 Pagecrinus by the apparent elimination of the infrabasals. 



The genus will probably be found to comprise only species of 

 small size. The dorsal cup is high, subcylindrical in form, and of 

 small diameter. The infrabasals are relatively large. The basals in 

 proportion to the dimensions of the cup are very large. The radials 

 are very small. In the type species the arms bifurcate typically on 



No. 2793.— Proceedings U. S. National Museum, Vol. 75. Art. 22 



40750—29 1 



