32 



SMITHSONIAN INSTITUTION 



PLATE XIII 

 (All figures natural size except where otherwise stated) 



PAGE 



. Figs. I, 2. Pycnosaccus tenuibrachiatus n. sp ■ 187 



Figs. 10, b. Left anterior and right posterior views of undistorted crown. Shows the small, short 

 arms, and straight horizontal margin of radials ; the surface markings are destroyed 

 by chemical action, only a slight trace of the radial ridges remaining. Author's 

 collection. 

 2. A larger specimen, somewhat flattened, with ridges fairly well preserved; from r. post, 

 radius. Author's collection. 

 Helderbergian, Keyser ; Lower Devonian. Keyser, West Virginia. 



Figs. 3-5. Pycnosaccus welleri n. sp 188 



Fig. ;}a. Nearly complete specimen with crown flattened, from r. ant. interradius. Shows the small 

 IBB and BB, very large RR, long arms, and 3 or 4 IBr. 

 3&. Left posterior radial view of crown; anal plate displaced. 

 3f. Restoration of crown in natural contour. 

 4a. Right anterior interradial view of a larger flattened crown. 

 4b, c. Posterior and hasal views of same. 

 Sa, b. Lateral and opposite views of much larger, crushed specimen. 



Niagaran, Brownsport; Silurian. Decatur County, Tennessee. 

 All the specimens are in the author's collection. 



Figs. 6-9. Pycnosaccus calyculus (Hall) 185 



Fig. 6. The type. Posterior view of calyx. Am. Mus. Nat. Hist, New York. 



ya. Specimen with arms and stem complete ; posterior view, showing curved anal plate above 



the line of radials, and the rounded arms. Author's collection. 

 76. Anterior view of same. 



8. Another calyx, showing form of anal plate. Author's collection. Lockport, New York. 

 90, h. Posterior and basal views of specimen from Chicago, figured by Weller as Lccanocrinus 

 waukoma, perhaps of this species. 

 Niagaran; Silurian. New York and Illinois. 



Fig. 10. Pynosaccus americanus Weller 188 



Fig. 10. The type. Posterior view of caly^x. University of Chicago. 

 Niagaran, Racine ; Silurian. Chicago. 



Fig. II. (?) Pycnosaccus dubius n. sp 189 



Fig. 1 10. The only specimen. It is complete, but the calyx plates are displaced, so that their arrange- 

 ment cannot be fully ascertained ; the anal side is entirely unknown. Author's 

 collection. 

 116. Outline restoration of plates as far as possible; showing IBB, BB, large RR, 3 short IBr, 

 and apparently no iBr. 

 Niagaran, Brownsport; Silurian. Decatur County, Tennessee. 



