PLATE 19, 20. 
fern and other vegetable remains, ironstone. 
FIG. 1 , 2 , 3 . 
PHYTOLITHUS (Osnmnda regalis) Filick fronde 
bipinnata: pinnis ovato-lanceolatis alternis patenti- 
bus : pinnulisovalibus integerrimis. S. p. 
A fossil vegetable. Original a Fern. Frond bipinnate. 
The pinn^ ovato-lanceolate, alternate, numerous and 
spreading. The pinnules alternate, oval, and very entire, 
(the terminal one generally larger and ovate) with croud- 
ed, dichotomous nerves, running from the midrib to the 
margin. 
Frequent near Chesterfield, Alfreion, &c. in bind and 
ironstone. 
This has been described by most writers on extraneous 
fossils; and by all, I believe, has been considered as a 
petrifaction of the Osmiinda regalis. As such I have named 
it ; though I confess myself doubtful, if the prototype be 
really the species in question. 
Fig. 1. Half of a nodule of ironstone, holding a speci- 
men of this fossil. 
2. A smaller nodule containing one of the pinnte. 
3. Another nodule with part of a pinna. 
