and Species of Crinoidea. 205 



Genus Sagenocrinites*, Austin. 



Def. — Dorso-central and perisomic plates unknown, as the 

 only portions hitherto discovered are the rays and plated in- 

 tegument, which extends between their lower divisions in the 

 same manner as the membranous web is stretched between 

 the toes of many aquatic birds. The peculiar construction of 

 these portions clearly proves them to belong to an undefined 

 genus. 



S. expansus, Phillips, sp. 



Mr. Phillips has defined this species as far as the existing 

 knowledge respecting it warranted in Murch. e Sil. Syst/ ; but 

 he has placed it provisionally with the Actinocrinites, to which 

 it in no respect appertains. 



S. giganteus, Austin. 

 Body-plates unknown. Rays unequally developed and va- 

 rying in their diameters ; secondary rays composed of a double 

 series of thin joints articulating by radiating striae as in various 

 columns. A plated integument connects the lower portions 

 of the rays. 



Family MEROCRiNiDiE, Austin, 

 contains the genera Dimerocrinites and Tetramerocrinites. 



Genus Phcenicocrinitesf. 



Def. — Dorso-central plates three ? First series of perisomic 

 plates, or those in the line of the rays, five ; second series five ; 

 third series, or ray -bearing plates, five and cuneiform. Between 

 these, the principal series, are several smaller plates, the num- 

 ber unascertained. 



P. simplex, Phillips ? sp. 



Def. — The arrangement of the perisomic plates agrees with 

 the generic type. Rays ten, composed of single series of joints, 

 and furnished with plumose tentacula. The column is short 

 as compared with Actinocrinites. No indication of auxiliary 

 side-arms has been observed in this species. Base furnished 

 with several fibres of attachment. 



This is supposed to be the Actinocrinites simplex of Phillips, 

 who states that " the pelvic, costal, and other plates of the body 

 agree with Miller's technical formula of Actinocrinites." We 

 cannot discover this agreement in any of the essential points, 

 and have therefore removed it into a new genus. 



Family Astracrinid^eJ, 



consisting of the genera Astracrinites and Aporocrinites. 



* From sagene, a fishing-net. t From phoinix, a palm-tree. 



I From astron, a star. 



