37 



size. There is an orifice on the azj'gous side of the central spine. 

 The ambulacral areas are raised into rounded ridges and the in- 

 terradial areas are depressed between the arms. The surface of the 

 plates, in our specimens, is destroyed and the larger number of 

 the sutures are not discei-nable. 



This species is distinguished, hj its general form, from all others. 

 The broad shallow calyx, high convex vault, and horizontal arms 

 will alone distinguish it. The number aud arrangement of the 

 arms is also a distinguishing feature as well as the surface of the 

 plates, for most species from rocks of the same geological age, 

 have highly convex or subspinous plates in the calyx. 



Found in the Hamilton Group, at Louisville, Kj'., and now in 

 the collections of the authors. 



AN INTERESTING LETTER. 



There is a letter, on file in the State Museum of Natural His- 

 tory of Illinois, belonging to the Geological Department, from 

 Charles Wachsnmth, dated, at Burlington, Iowa, August 9, 1892, 

 containing the following paragraph: 



" I have described the Eiirnlyi:>tocrinns lindahli and have sent 

 the description, together with that of some other new species from 

 the Niagara Group to the American Geologist for early publication, 

 to secure priority, as I am aware that S. A. Miller will be out 

 this fall, on some of the same S2)ecies. This, of course, is confi-' 

 dential, for I do not want Miller to know it." 



There was no more sympathizing place, for the publication of 

 such material, than the American Geologist, a journal that never 

 aspires to a higher level in scientific matters. 



-6 G. 



