278 Glyptocrinus Shafferi. 



on the upper sloping sides, the free rays of the crinoid. The radials 

 form a longitudinally convex elevation above the interradials, which 

 give the short body a somewhat pentagonal appearance. 



Only three interradial plates appear in the figure, and, though I 

 have examined several, otherwise, very good specimens, I have been 

 unal)le to discover the outlines of more than three plates ; but from 

 these examinations, I am led to believe, that there are six interradial 

 plates or minute pieces arranged about as in other species ofthis genus. 



Arms rise free from the third radial, cylindrical on the outside. 



Fig. 20. Glyptocrinus Shafferi, magnified 23^ diameters. 



bifnrcate, in one specimen on the twelfth plate and in another specimen 

 on the ninth plate ; (the figure was made from the latter specimen, 

 but by mistake only seven plates appear in each of two rays) ; and 

 run to a point, from twenty to thirty pieces distant without another 

 division. Each plate or arm piece supports, on a shoulder, on one of 

 its inner lateral sides a comparatively large and strong pinnule. The 

 pinnules are alternately arranged on the inner lateral sides of the arms 

 and are composed of pieces three or four times as long as wide. 



Column large, compared with the size of the pelvis; composed, near 

 the head, of alternately thicker and thinner pieces, but a short distance 

 below the head, three, four or more thin plates intervene between the 

 thicker ones, presenting the appearance of a string of little spools. 



This species is di>tinguished from others, by its small, smooth body, 

 coarse pinnules, and free arms, above the third radial. The cup 

 terminates with the third radial. The column is distinguished from 

 any other in our rocks, by the distance between the larger plates, 

 which gives it the appearance of a string of little spools. 



The range seems to be about the same as that of G. decadadylm, or 

 between 300 and 450 feet above low water mark, at Cincinnati. It is 

 quite rare among the collectors, only a few specimens having been thus 

 far found. 



The specific name is given in honor of D. H. Shaffer Esq., who 

 found the specimen figured above, and kindly gave it to me, for 

 examination and description. It is a very handsome free specimen, 

 with all the arras and pinnules folded together, but the figure was 

 engraved from a photographic view% Avhich elevated the lower part of 



