PLATE. X17. 
Page 
Fias, 1-6. ASPIDIUM FREDERICKSBURGENSE, Sp. NOV ...----. .----. -------- Oncrion ocosoces son0 94 
1. Portion of a compound pinna or of the frond. ..---....--..----..---- SoRnScobdosse 94 
1°, Pinnule of 1 magnified to show the nervation.............---.-.---.---.---------- 94 
2) Portion of an ultimate pinna showing S0rl: =.= 2-22. 5. occ. woe nee oon emit nie 94 
Qa" Pinnuleiof 2-magnified to show the sori —- <= —- 22 2-26. oo nae wee = eee 94 
Qbs-AvsOrus stil morenm deni eden. aise esas sae eee eee) Peel aa eee eee eee 94 
3. Fragment of a very long ultimate pinna...-.......... 222-250. ------ --- eee enn--- 94 
ait WEY G IGG AWE Brecocens os ee pbenss.dasces cap 266 on s= Sh soos Se Sy See eso SEESSOS 94 
4. Fragment of an ultimate pinna with distant ninnitles Sate shestele ses eieeloe eee sare 94 
eye Pinn] eyolesom we neds sien ects eer cee ae eek ake alee nine ee eel eel 94 
5. Fragments of ultimate pinnae with entire margins --..-.-.-.---------------------- 94 
6. Fragment showing unusually small pinnules-.......--....-------------.----------- 94 
6°, Pinnule of 6 magnified to show nervation ...-.......--------------------- Scpchecee 94 
PIGS Gio: | OCUADOPHDEBIS 2A CUDAGISD silt O Vises aie aae = a sete alee lene pee ree ee ete ae 74 
7. A form with unusually long and slender pinnules-....--. .--..-----------+++------ 74 
72) PinnuleoL magnified to Show, DGLVAtlON == se cer eee a eae aeons eel eae ele 74 
8. Portion of the frond or of a compound pinna ...-....--..----.-------------------- 74 
8°, Magnified pinnule of 8...........---- ------ «----- o---- 6 cacs06 PE Ee cam EEO COCO COOE 74 
