36 



they are long and composed of long, slightly cuneiform, alternately 

 projecting plates. Eacii projecting joint bears a small pinnule, 

 which does not prevent the arms from closing tightly around the 

 proboscis. 



The azygous area is not large in this species. There is only 

 one plate within the calyx, and it broadly truncates a subradial 

 and separates two first radials. There appear to be two plates 

 succeeding this one, but the arms in our specimen prevent 

 further examination of the plates. 



This species is peculiar in its long, delicate form, closed arms, 

 long brachials and constriction above the calyx. The axygous 

 area is also peculiar and we know of no species with which it is 

 necessary to make any comparison in these particulars. 



Found in the Kinderhook Group, at LeGrand, Iowa, and now 

 in the collection of Wm. F. E. Gurley. The specific name is 

 given in honor of Mr. L. A. Hammond, an enthusiastic collector 

 of LeGrand, Iowa. 



POTEKIOCRINUS MACCABEI V(ir. DECKEPITUS, n. Sp. 



Plate I J I, Fig, 9, azygous side of (i, depressed and someivhat in- 

 jured specimen magnified two diameters; Fig. 11, same, 

 jiaturel size; Fig. 10, posterior view two diameters; Fig. 

 12, same, natural size; the posterior view of another 

 specimen, magnified and natural size, may be seen 

 on Poteriocrinvs jnaccabei in Figs. 5 and (I. 



This is a small species beaiung short rugged arms. Calyx ob- 

 couoidal as seen from the posterior side, but unsymmetrical on 

 account of the development of the azygous area. Diameter one 

 half more than the height; plates smooth; column small, round. 



Basals small and superior angles somewhat obtuse. Subradials 

 one-half wider than high, except the one on the azygous side, 

 which has a length about equal to the greatest width; four of 

 them are hexagonal, the other two are heptagonal. The azygous 

 subradial, which is truncated at the top, is heptagonal and the 

 largest plate in the calyx. The other heptagonal plate is on the 

 right of the azygous area, but is not larger than the hexagonal 

 plates- First radials, one-third wider thau high, quite convex 

 longitudinally, which leaves the separating sutures much depressed 

 pentagonal, and truncated the entire width above, where the 



