KNOWLTON: THE STUDY OF FOSSIL FERNS 105 
The study of fossil ferns | 
F. H. KNOWLTON 
On first thought it may seem that the student of living 
ferns has many advantages over the student of fossil 
collects his Patel in the field, has the opportunity of 
examining it to the minutest detail, from the ecological 
conditions under which it grew, its internal anatomy and — 
are to its frond outline, nerve characters, and 
< ruit production. If it be worth while it may be grown © 
ee. anilicadiy through its. complete life cycle back to the 
See spore-producing stage again. Yet, in spite of this seem- — 
ing perfection of detail, all students well know the differ- 
ences of interpretation that constantly arise. From the 
limits of families, genera and species, to the faintest 
eee and hybrid, waa: are, or may be, oypoare : 
riews. oS 
When a botanist without previois experience along 
these lines views a collection of fossil ferns he is very apt) =| 
to say, that, beyond the fact that they appear really to. 
be ferns, little or nothing can is dor Ly 
rectly placing them, even 
ans Veena. 
experience, coupled with 0 a k 
