WARD.] THE JURASSIO FLORA. 837 
tome. Besides this, the notice by Dr. Newberry of the fossils found by him with 
these, but not figured, adds to the doubt in my mind. 
The plant figured in figs. 1 and 2 is certainly not a Cyclopteris. It is probably a 
fern and, ifso, has quite a modern look, resembling more than others some of the 
living Adiontus, For shape it may be compared with the living A. asarifolium 
Willd., and for the possession of a basal midrib, with the living A. Wilsoni Hook. 
It may, however, be some old Proteaceous type, for it has something of the habit 
of a dicotyledonous leaf. 
Figs. 3 and 4 probably represent a Gleichenia, and they look something like some 
of Heer’s forms from Kome, with, however, decided differences. If I were com- 
pelled to determine the age from the figured plants alone, I should say it is lowest 
Cretaceous or Neocomian. 
Newberry says that the dicotyledonous leaf given in fig. 6 comes frou the lignite 
beds that furnished the other plants of the flora now in question (see p. 131, under 
Phyllites venosissimus.) 
The nervation and shape of this reminds me of some of the forms of Sapindopsis 
of the Potomac. If this leaf was really found in the lignite bed, and not higher up 
in the Dakota group, its evidence would point to a Cretaceous age. 
In connection with this I may refer to what Newberry says at the top of page 131, 
in closing his remarks on his Pecopteris cycloloba, the possible Gleichenia. He says 
of this plant that it is associated with Clathropteris of Jurassic affinities, and the first- 
appearing species of the dicotyledonous plants of the Cretaceous epoch, etc. He 
does not put the lignite bed and underlying strata in the same group with the beds 
of the uppermost mesa, which yielded him dicotyledons, so that I infer that he means 
to say that he found dicotyledons with P. cycloloba, but I can not understand why 
he does not lay stress on that fact. Again, on page 132, he mentions finding Cla- 
thropteris in the lignite bed, yielding the above-mentioned plants, but he says that 
the fragments were too imperfect for description. If this is in fact a Clathropteris, 
then it would indicate strongly that the age of the bed is Jurassic. I would suggest, 
however, that under some conditions a Clathropteris might, if imperfectly preserved, 
be similar to some imperfectly preserved dicotyledons, and these fragments may 
be really no more Clathropteris than the dicotyledonous leaf given in pl. iii, fig. 
5 is a Neuropteris. 
Dr. Newberry, in his letter to you, in which he says that the plants were obtained 
in No. 15 of the section on pages 84, 85, seems to have forgotten the section obtained 
at camp 92, before reaching the Moqui villages, given on page 81, where he found the 
same plants as in No. 15, and he overlooked the statement made at the bottom of page 
131, which attributes Phyllites venosissimus to the same lignite bed. He says in his let- 
ter that only the plants figured in Nos. 1 to 4 comefrom thishorizon. Are we to take 
his present recollections or his statement made then? Of course the presence of this 
dicotyledon may be accounted for by supposing that it came really from the Cretace- 
ous strata above, but got mixed up with the lignite plants. 
Have you noted the fact that Newberry, on page 131, says that his Phyllites venosis- 
simus, pl. iii, fig. 6, comes from the beds with the supposed Jurassic plants? This Phyl- 
lites is apparently a dicotyledon like the Potomac Sapindopsis. Is what he says of the 
Clathropteris, page 132, all that is known of it? I wish I could feel sure that it is really 
a Clathropteris. It may be no more that plant than Neuropteris angulata, pl. iii, fig. 
5, is a Neuropteris, for this is a small dicotyledonous leaf. 
Now, if the supposed Clathropteris is really one, it would be worth more than his 
Cyclopteris and Pecopteris in deciding age. All the supposed Jurassic plants seem to 
come from No. 2 of the section at camp No. 92 (see p. 81). 
Lam afraid that Cyclopteris moquensis (which is of course no Cyclopteris) and Pecop- 
teris cycloloba will be of no helpin making out age. Has it occurred to you that the 
plants may be Potomac? 
20 GEOL, PT 2——22 
