FOSSILS OF THE CHESTER GROUP. 551 



piece : each composed of a singly series of wedge-shaped 

 pieces, alternately longer and shorter on opposite sides, but 

 not protuberant on either side; those near the lower part 

 about as long on the longer side as their breadth. Tenta- 

 cles numerous, rather stout, and composed of joints three 

 or four times as long as wide, and not swollen or dilated 

 at the ends. 



Column round, of moderate thickness near the base, 

 where it is composed of alternately thicker and thinner 

 pieces. Surface apparently smooth. Sutures between the 

 lirst and second radial pieces distinctly gaping, when the 

 arms are folded together. 



Hight of body to top of the first radial pieces, 0.25 inch; 

 breadth of do., 0.48 inch; length of arms above the second 

 radials, at least 1.90 inches, and probably more ; diameter 

 of column at its connection with the base, 0.13 inch. 







This species seems to be closely related to 8. decabracliiatus. Hall, 

 (Iowa Eeport, Vol. I. Part IE, p. 679, pi. xxv, fig. 1,) but it is larger and 

 more robust, -and its second radial pieces differ materially in form, iu 

 being nearly or quite twice as wide as long, instead of "nearly once 

 and a half as long as wide." Its body is also much more rapidly ex- 

 panding upwards, and its basal pieces proportionally about twice as 

 large as those of 8. decabrachiatus. Other corresponding differences 

 would doubtless also be apparent on comparing specimens of each 

 showing all the parts. 



Lm-ality and position Bay City, Pope county, Illinois. Chester di- 

 vision of the Lower Carboniferous series. 



SCAPHIOCRINUS RA^DOLPHENSIS, Worthen Ms. 



PI. 21, Fig. 14. 



BODY rather small, depressed-obconical below the second 

 radial pieces, rapidly expanding from the base; plates rather 

 thin, their surfaces covered with flattened granules. Base 

 short, scarcely one-fourth as high as wide, columnar facet 

 covering more than half its entire width. Subradials 

 nearly equal in size, four pentagonal, and one hexagonal. 



