FOSSILS OF THE KEOKtJK GROUP. 491 



hexagonal, and one on the anal side heptagonal. First 

 radial* as wide as the subradials, but shorter, pentagonal 

 and truncated their entire breadth above. Second radials 

 as wide as the first, but scarcely more than half as long, 

 all transversely oblong in form. Third radials in the pos- 

 terior and anterior lateral rays, of nearly the same form and 

 size of the first, but of course with sloping sides above. 

 On these sloping sides they each support two unequal arms, 

 the posterior one of which in one of the posterior lateral 

 rays is smaller than the other, and can be seen to bifurcate 

 on the fourth piece, while the other bifurcates on the second 

 piece, and its subdivisions divide again at various distances 

 above several times, so as to make altogether about thirteen 

 or more subdivisions in this ray. The anterior main di- 

 vision of one of the anterior lateral rays can also be seen 

 to bifurcate on the fifth piece above the third radial, and 

 one of its branches subdivides at different distances above 

 into three subdivisions, and the other into four. Anterior ray 

 simple to the eighth piece, the pieces between the first and 

 last being short and somewhat wedge-form, while the last 

 is pentagonal, and supports two arms, each of which can 

 be seen to bifurcate at least once some distance above. 

 Anal pieces with the usual double, alternating arrange- 

 ment, the lowest piece being obliquely inserted between the 

 upper sloping sides of two of the subradials, and partly 

 under one side of one of the first radials, while a con- 

 tiguous piece on the left above is supported on an upper 

 truncated side of one of the subradials, and the latter are 

 succeeded by others that connect with the base of the pro- 

 boscis. Arms long, slender, straight and gradually taper- 

 ing: slightly convex on the dorsal surface, and flattened so 

 as to fit closely together on each side, with all their di- 

 visions running up parallel, or showing scarcely any diver- 

 gence at the bifurcations, and all composed of short wedge- 

 formed pieces; axillary pieces not more protuberant than the 

 others. Piunula? small, and arising one from the upper 



