404 llie Calceocrinidce. 



follows the suture-line of the anterior anchylosed basal, and incloses a 

 lunate space between it and the other groove. The third groove starts 

 at the columnar foramen and crosses the second groove, passing across 

 the middle of the anterior anchylosed basal to the anterior margin, 

 where it is all that remains of what was probably once a suture-line. 



From the lower third of the Niagara Shale at Middleport-., 

 2i. Y. 



This basal piece is readily distinguished from the one be^ng- 

 ing to (7. typus by not presenting an evenly circular posterior 

 outline, and by the anterior consolidated basal extending to the 

 extreme outer angles. The rest of the calyx has not to my 

 knowledge been found. This species has been named in honor 

 of Professor James Hall, who was its original discoverer and 

 who based the genus upon it. 



Calceocrinui bi<leiitalu§ n. sp. 



PI. X., Fig. 10. 



Anterior portion of the calyx flattened, quadrangular in outline, with 

 a slight depression along the median suture-line. The lower margin of 

 the calyx bears upon its upper surface three semicircular depressions 

 with sharply defined margins. The median one of these is the widest 

 and has a smaller one with a sharper curvature on either side, leaving 

 two sharp dentate projections between. Anterior basal high and but 

 little more than half as wide as the base; its two suture-lines commence 

 in the lateral depressions or cicatrices. Anterior brachial projecting^ 

 somewhat beyond the upper angles of the lateral basals, and having^ 

 its upper margin slightly curved downward for the reception of the 

 anterior arm. 



The outer sides of the lateral radials project but little on the posterior 

 side of the calyx. 



This species is of the type of calceocrinoid structure to which C. stig^ 

 matus Hall belongs, but is at once distinguished from it by the nar- 

 rower anterior radial, and the fact that the suture-lines of it commence 

 in the lateral cicatrices, instead of passing to the outside of them; vari- 

 ous other minor differences can be noted, but the above will prove suf- 

 ficient for diagnostic purposes. 



From the lower third of the Niagara Shale at Lockport, N. Y. 



Calceocriiius contractus n. sp. 



PI. X., Fig. 12. 

 Consolidated basal piece quite convex posteriorly. 

 Posterior margin truncate. Anterior anchylosed basal extending 



