388 Dr. F. A. Bather on British Fossil Crinoids : 



1833, named Balanocrinus first by L. Agassiz (1845) on 

 erroneous characters. 



It Avill be seen that the distinction of Balanocrinus from 

 Isocrinus lies in the arr.angement of the crenellae on the 

 normal joint-face: "quinae striae punctulatae a centro 

 versus peripheriam protensae, cum Halone seu ambitu 





Figures 1-4. Balanocrinus didactylus. 



1. Normal joint-face. E 21948. 



2. Syzypiai joint-face of epizygal with two cirrus-facets. E. 22027. 



3. A cirrus-facet, seen from tlie angle of the ossicle. E 22027. 



4. A hypozygal notch, seen from the aiigle of the ossicle. E 22027, 



Figures 5-7. Balanocrinus suhbasaltiformis, 



5. Normal joint-face. E 5887 6. 



6. Young joint-face with more ZsomnMS character. E 426 a. 



7. A cirrus-facet, seen from the angle of the ossicle. 67543 c. 



All figures enlarged 4 diameters. 



crenato/' as Scheuchzer so well expressed it under the 

 heading "Asteria columnaris Entrocho similis^' (1702, 

 ' Specimen Lithogr. Helvet.,' pp. 2-4., pi. - figs. 1-5). In a 

 well-preserved characteristic specimen this is clearly marked, 

 but there is reason to believe that in young stages, or even 



