Fossils of N. E. Missouri.—kowley. 309 
these have heavy spinous nodes, especially those ambulacrally 
located. The anal tube is rather small and a little eccentric 
in position. 
The arm bases form five rather strong lobes, the right and 
left posterior ones having three arms each while the anterior 
ray supports but two and the right and left antero-lateral 
four each or sixteen in all. Column small and round. This 
little fossil has some affinity with Lobocrinus. 
From the fourth division of the Lower Burlington limestone, 
Pratt’s quarry, Louisiana, Mo. 
Eretmocrinus brevis, n. sp. 
PLATE XVIII. 
Fics. 15, 16. Anal side and basal views of the type. 
Dorsal cup low and greatly expanded. Basal plates form 
a truncate lower surface with sharp outer edges but no con- 
vexity beyond the body surface. The column is small, round 
and with a small circular canal. The first radials are much 
wider than long. The second radials are quadrangular and 
twice as wide as long. The third radials are pentagonal and 
wider than long. The second radial series consists of three 
very wide plates, to the arm bases. The interradial area seems 
to be filled by but one large plate. The first azygous interradial 
supports three smaller plates above and upon these latter rest 
two or three small elongate pieces. The plates of the dorsal 
cup are without apparent convexity. The ventral disk is low 
and the plates hardly convex except one near the center ot 
each ambulacrum which supports a small acute spine. Anal 
tube eccentric. 
The periphery is separated into five lobes of two arm bases 
each, except the right posterior ray which supports three, mak: 
ing eleven arms in all, unless the rays bifurcate beyond the 
body. This is the most depressed form of Eretmocrinus yet 
described. 
It is from the Upper Burlington limestone of White Ledge, Mo.., 
and the type is in the author’s cellection. 
Spirifer pikensis, n. sp. 
PLATE XVIII. 
Fic. 17. View of the cardinal edge with the brachial valve turned 
somewhat obliquely to the observer. Natural size. 
Fics. 18 and 19. Views of the pedicel and brachial valves, respectively, 
one-half diameter. 
