262 DlCl'YOSPONGIDJE. 



PLATE XXXII. 

 CRYPTODICTYA, Hall. 



Page 144. 

 (See Plate XXXI.) 



Cryptodictya Alleni, HalL 



Page 144. 

 (See Plate XXXI.) 



Figure 1. The nodose portion of a large specimen. This appears to have 

 been a lateral or extremital portion of a frond where the surface is 

 marked by obliijue angular curved lidges teiTuinatiug in swoUen 

 nodose elevations. Several of these ridges show coarse lines or 

 grooves radiating from the summit, and over the broad general slope 

 of the surface as well as between the ritlges are seen traces of 

 spicular lines. 



Figure 2. A small fragment representing a partially enfolded, narrow portion 

 of a frond, bearing a divided node on the surface. 



Figure 3. A specimen of subclavate outline, exhibiting the flattened nodose 

 surface, the sides falling away vertically in all directions, except 

 below. These specimens all indicate that the original form of the 

 frond was a suboval expansion having a slight elevation, a nodose 

 upper or expanded surface and probably was attached by the free 

 margins or by the narrowed extremity. 



Figure 4. A somewhat similar portion of a frond showing the irregularly 

 nodose surface. The margins of the expansion are bent vertically 

 downward on all sides except the postenor and the specimen appears 

 to be the elevated and flattened surface of the frond. 

 Chemung group. Neai- Lyndon, Cattaraugus county, New YorJc. 



