ON CAEBONIFEfiOUS ENCRINITES. 477 



The hasals are five, as described by De Koninck and Major Austin. 

 They articulate to the column by radiating ridges and furrows. 

 Sometimes at the points they are lowered, so as partially or entirely 

 to overlap the top point of the column. 



The five subradials are well described by De Koninck and Major 

 Austin. All their edges articulate by ridges and furrows at right 

 angles to the surface of the plate. 



The radials are seven in number; of these the first only was 

 known to the above-mentioned authors. These first radials articulate 

 to the subradials by ridges and furrows, but this is not the case 

 with their lateral articulations to one another. They are followed 

 by six radial plates, and a cuneiform one, where the first bifurcation 

 takes place. Then follow twelve hrachial plates and a cuneiform one 

 to the second bifurcation; then an uncertain number, not less than 

 twelve, to the third bifurcation ; and then eighteen and a cuneiform 

 to the fourth bifurcation. The number of rays is thus eighty. 



All the plates of the arms are more or less laterally wedge-shaped, 

 with the thick end of one fitting the thin end of the next. Up to 

 the second bifurcation they all articulate by radiating ridges and 

 furrows, and the rest probably do the same. This articulation of 

 the arm-joints has not commonly been observed. 



The anal plates are five in number, while De Koninck gives for 

 the genus 4 or 6, and they do not agree with his generic figure. 

 They are arranged in two vertical rows ; the two lowest are penta- 

 gonal, the two next are hexagonal ; the last is probably hexagonal. 

 {See plate VL.fig. 2.) 



The proboscis is by far the most interesting part of this species, 

 being composed certainly of upwards of 1000, and probably of upwards 

 of 1300 separate plates, and exhibiting a structure hitherto undes- 

 cribed amongst the Crinoids. Professor De Koninck, speaking of the 

 probosces of the Crinoids, says that some are formed of many 

 hexagonal plates, as Foteriocrinus gracilis, (M'Coy), others are mem- 

 branous and formed of a single piece. As he does not describe any 

 membranous ones in his work. I fancy he may have got this notion 

 from Austin's figure of P. crassus, or perhaps from a Clevedon 



