3866 OLDER MESOZOIC FLORAS OF UNITED STATES. 
Macroteniopteris is a type of fern that, in typical forms, can not 
be mistaken for any other. Its range in time seems to have been from 
uppermost Trias to Oolite, reaching its maximum development, if 
Feistmantel is right as to the age of the Rajmahal series, in the Lias. 
Now, although the amount of material obtained showing it in the 
Oroville flora was not large, it was evidently a conspicuous plant in 
that flora. The most common species, I californica, is nearer 
Macroteniopteris ( Teniopteris) lata of the Rajmahal flora than any 
other plant. JL nervosa is unique. Even if neither of these species 
bore any resemblance to known forms, the very fact that Macro- 
teeniopteris is an important type in a flora is evidence favorable for 
the age being Jurassic. 
The common Teniopteris in the Oroville flora is so near Z. tenut- 
nervis, the characteristic one of the Infralias (Rhetic) of France, 
that it may be considered its representative, modified by differences 
in its surroundings. As this is a common type as late as the 
Oolite, its presence need not indicate an age greater than the Lias. 
Cladophlebis densifolia, if it bas any relationship to known species, 
is best compared with Pecopteris lobata Oldh., of the Rajmahal 
series. 
Adiantites orovillensis seems to be unique and not very near any 
known species. The Angiopteridium has A. McClellandi of the 
Rajmahal series as its nearest plant. 
The three new species of Ctenis belong to a type that begins in the 
Rhetic with the peculiar C. fallax of Nathorst and exists in the basal 
Cretaceous in at least one species, C. dmbricata Font., of the Potomac 
of Virginia. Except in its inferior size, the Oolitic plant of Lindley 
and Hutton, Ctenis falcata, seems to be the form nearest to the Oro- 
ville type. 
It should be noted, however, that in their general facies these plants 
are close to the large Pteraphy lla of the Rajmahal series, the anasto- 
mosis of the nerves, which may be a special development, being the 
principal difference. 
The large Ctenophylla were evidently common and very important 
plants in the flora. Ctenophyllum densifoliwum and C. grandifolium 
Storrsit were related to the C. grandifolium of the Virginia older 
Mesozoic, the variety Storrsit being near enough to be regarded as a 
variety of the latter. 
The small Crenophylliim angustifolium has probably a near relation- 
ship to another Older Mesozoic plant, viz, C. Braunianum. 
Carpolithus Storrsti appears to be unique. So far as any relation- 
ship can be made out for it it is with a Jurassic plant. 
Putting the Oroville plants in the form of a table that shows the age 
of the plants nearest to them or identical with them, we may denote 
