PLATE I, 



PAGE. 



Tig. 1. F'ENESTELLA KEGALIS Ulr. (Bee also PI. LIV) 538 



1. Portion of the obverse face of a nearly complete frond, x9, showing rela- 

 tive size of branches, dissepiments, andl fenestrules, and the strong 

 carina. 

 1 <i. Reverse aspect of a frond, x9. 



Keokuk group. Kings Mountain, Ky. 

 E. O. Ulrich's collection. 



Fig. 2. FENESTELLA COMPBESSA var. NODODOBSALIS Uh- 540 



Portion of I he reverse face of a large frond, x!>, showing the strong 



irregular nodes and the relative size of the branches, dissepiments and 



fenestrules. 



Keokuk group, Kings Mountain, Ky. 



E. O. Ulrich's collection. 



Fig. 2 a. FENESTELLA COMPBESSA Ulr 539 



The obverse side of a very perfect example, x9, showing the narrow 



branches, prominent carina with its row of tubercles, and the angular 



dissepiments. 



Keokuk group. Kings Mountain, Ky. 



E. O. Ulrich's collection. 



Fig. 3. FENESTELLA MULTISPINOSA Ulr 540 



3. The obverse face of the basal portion of a frond, x9. 

 Keokuk, Iowa. fi. O. Ulrieh's collection. 



3 a. The reverse side of same, x9, showing rounded feuestrules and the 

 numerous granules on both the branches and dissepiments. Farther 

 out on the fronds the dissepiments are thinner, the fenestrules more 

 nearly subquadrate and the branches appear straighter. 



3 b. Thin section, x!8, showing structure of the dense substance on the re- 

 verse. 



3 c. Obverse face of a frond sh owing the appearance near the free mar- 

 gin, x9. 



3 d. Thin section of a specimen with slightly larger fenestrules th-m usual, 

 x!8. Shows the minute structure at different levels. 

 Kookuk group, Kings Mountain, Ky. 

 E. O. Ulrich's collection. 



