53 



The pinnulri-bearing arm pieces are swollen or c'aviform at the joints, 

 which are oblique so that the articular facet of the two arm pieces and 

 the articular facet of the arm piece and pinnule are at right angles to 

 one another. 



The left posterior X'adial (or anal) piece carries the basal plate of a 

 ventral tube of which but three pieces can be made out in the typa 

 specimen, owing to the folding of the arms over the upper portion. 



Collected by the author at Division Street, Ottawa, in beds of the 

 Trenton Formation. 



CALCEOCRINUS Rt'GOSUS, n. Sp. 



This species has the same arrangement of the plate-s of cup and 

 arms as C. fiircilUitus, excepting that the central arm of the anterior 

 side of this species does not appear to be bifurcated ; there being in the 

 only specimen which I have examined five ])lates of the i>rim:iry 

 series but no axillary piece. 



In the specimen described, the basals, radials and arms, are all in 

 the sane straight line, so that both sides of the basal plates can be ob- 

 served. A piece of the column which was in the same line as the other 

 portions was lost while cleaning the specimen. 



The basals at the lowest point have a broad facet for the articula- 

 tion of the column, and from thence a marginal lip is carried each edge 

 of the posterior side, across which a ridge is carried, immediately 

 opposite the vertical suture of the anterior side, to the middle of the 

 line of articulation with the series above, thus dividing the posterior 

 side of the basals into two concave surfaces. The posterior side of tlie 

 basal series shows no sutures. 



All the plates have punctate surfaces. 



The primary radials have each a deep transverse furrow which 

 with ridges at the s\itures produce wrinkles. The arm-plates and 

 pinnules are stouter than in C . furcillatufi. 



Collected by Mr. W. K. Smith at Belleville, Out., in a stratum of 

 the Trenton Formation, containing Porocrinus Smithi, Pleurocijstites 

 quimosiis, Dendrocririus Jewettii, ifec. 



DKXDROCRINUS PROROSCIDIATUS, BILLINGS, 1857. 



The sj)ecimen figured was discovered last autumn, at Division 

 street, this city, by Mi-. Wm. H. Jenkins of Madoc, Ont., who kindly 



