418 PALEONTOLOGY OF ILLINOIS. 



PinnulaB stout, arranged at intervals of near their own 

 breadth apart, and composed of joints that are about as 

 long as wide. Surface granular; body plates even, and 

 merely separated by linear sutures. Column of compara- 

 tively moderate size, faintly subpentagonal near the base, 

 and composed of rather thin, nearly equal plates, with a 

 very small central perforation. 



Hight of body to the top of first radial pieces, about 0.12 

 inch ; breadth, 0.20 inch ; length of arms, about 0,75 inch ; 

 thickness of column at base, near 0.07 inch. 



This species is related to the last two, but is readily distinguished by 

 the more conical form of its body, produced by the protuberance of its 

 base, as well as by having two arms to each ray all around, instead of 

 only one in the anterior ray. It also differs from both in having its 

 body plates even, instead of very convex, or tumid, as in S. scalaris, or 

 costate, as in S. Jiscellus. 



Locality and position Lower division of the Burlington group, at 

 Burlington, Iowa. Lower Carboniferous. No. 284 of Mr. WACHS- 

 MUTH'S collection. 



ScAPHiocRraus STEIATUS, M. and W. 



PL 2, Fig. 11. 

 Saphiocrinus striatus, MEEK and WOKTHKN. Proceed. Acad. Nat. Sci., Phila., 1869, p. 142. 



BODY below the top of the first radial pieces subhemis- 

 pherical, being regularly rounded below ; composed of thick 

 plates, which are ornamented with distinct, somewhat bro- 

 ken striae, running vertically, so as to radiate from the base, 

 but all parallel with each other on each individual plate. 

 Basal pieces hidden by the column externally. Subradials 

 about as wide as long, five of them showing a pentagonal 

 outline (there being no visible angle at the middle of their 

 bases on the outside), and one on the anal side hexagonal, 

 the latter being a little larger than the others. First radial 

 pieces slightly shorter than the subradials, but about once 

 and a half as wide, all having a general pentagonal form, 

 being broadly truncated their entire breadth above, and 



