FOSSILS OF THE BURLIXGTOX GKOUP. 411 



Beyond these bifurcations, it is evident from the number 

 of slender branches seen that there must be other subdi- 

 visions, but the specimen is not in a condition to show the 

 details of the bifurcations. Arm pieces generally longer 

 on the longer side than wide, but not arranged in zigzag; 

 the first two of each arm twice as long as wide, and some- 

 what contracted around the middle. Proboscidiform ex- 

 tension very long, or nearly or quite equaling the length 

 of the arms, anH somewhat narrowed at the extremity. 



Surface of the first radial plates strengthened by prom- 

 inent, rounded, radiating costa?, two of which diverge down- 

 ward from the mesial prominence under the sinus for the 

 second radials, to connect with others on the subradials, so 

 as to inclose profound triangular pits at the upper corners 

 of the latter; while two similar ridges run laterally on each 

 side of the sinus, parallel to the upper margin, to connect 

 with those similarly situated on each adjacent first radial. 

 On each subradial the ridge extending down the middle 

 widens, and becomes nearly obsolete at the base, where it 

 connects with several slender lines that continue on down, 

 converging toward the lower part of each basal piece ; there 

 being no pits or impressions at the meeting of the corners 

 of the basal and subradial pieces. 



Hight of body to the top of the first radial 0.96 inch; 

 breadth across at the most protuberant part of the first 

 radials, about 1 inch; length of arms from their origin on 

 the second radials, about 4 inches ; length of proboscidi- 

 forni ventral extension, 3.85 inches. 



This fine species departs very widely from the typical forms of Scaphi- 

 ocrinufi in its large size, obconic body, strongly costate body plates, long 

 bifurcating arms, and particularly in having its second radial pieces so 

 narrow, in proportion to the first, as to be separated from each other by 

 interradial spaces wider than the second radial pieces themselves. Its 

 anal series, although including more pieces than we see in the typical 

 ScapliifH-rinus (being like that of Poteriocrinites proper), does not differ 

 from that of a large proportion of the species usually included in Scaplii- 



