PALEONTOLOGY. 



FOSSIL FLOEA. 



Columbus, Ohio, Febniary 28, 1872. 



Dear Sir: In accordance with your instructions I have prepared 

 the following report on the specimens of fossil plants obtained in your 

 geological explorations of 1871. I regret that the time allowed to me 

 for the examination of such a large number of specimens, (more than 

 three hundred,) and the preparation of the report, was too short. This 

 may account for, if not excuse, the deficiency of this paper. 



The first part of the report contains the descriptions of eighty species 

 of fossil plants, mostly of the Tertiary formations. To obviate the want 

 of plates and figures, I have quoted largely from already described and 

 figured species, either analogous or identical, this being the best way 

 to give an idea of the forms of leaves, always more or less obscurely 

 conceived from mere descriptions. 



The general remarks on geographical, stratigraphical distribution, 

 typical comparisons, &c., which form the second i^art of the report, are 

 presented as a mere summary of questions which should be elucidated 

 with more details when your fossil plants of the recent formations are 

 published in a general report, and the descriptions illustrated with 

 figures. 



Yery respectfully, yours, 



L. LESQUEREUX. 



Professor F. V. Hayden, WasUngton, D. G. 



I.— ENUMEEATION AND DESCEIPTION OF THE FOSSIL 

 PLANTS, FEOM THE SPECIMENS OBTAINED IN THE EX- 

 PLORATIONS OF DR. F. Y. HAYDEN, 1870 AND 1871.* 



1. Henry's Fork. 



Hard silicified limestone, with indistinct remains. 



Pteris penn^formis, Heer. A number of broken specimens of the 

 fern referable to this species, have been re-examined, without affording 

 more evidence to what has been said in the former report, p. 384. It 

 differs from the following species, found also on broken specimens of 

 this locality, by its thicker secondary veins, more obliquely attached to 

 the medial nerve, and by its entire borders. 



Blechnum Gopperti, Etting, (Flor. Bil., p. 14, PL iii, Fig. 1-4.) 

 Fragments of linear leaves, half an inch broad, with dentate borders ; 

 secondary veins nearly in right angle to the thick medial nerve, paral- 

 lel, forking once near the base, and much thinner than those of the for- 

 mer species. Though the specimens show mere fragments of leaves, 

 the specific characters are well marked. 



A third species of fern is preserved on the shales of this locality. It 



* See Report of the Territories, 1870, p. 384. 



