1890.] 69 [Lesley> 



His "Tertiary Plants of Mississippi " appeared in Hilgard's Report of 

 1863. 



His "Cretaceous Flora of the Dakota Group" appeared as a mono- 

 graph in 1874, as a "Report of the U. S. Geol. and Geog. Survey of the 

 Territories" under Dr. Hayden. 



His monograph of the "Pliocene Flora of the Auriferous Gravel De- 

 posits of the Sierra Nevada" appeared in 1875. 



His "Tertiary Flora " as a monograph in 1878-. 



His "Cretaceous and Tertiary Flora" as a monograph in 1883. 



" The Coal Flora of Pennsylvania and the United States," Report P of 

 the series of geological reports of that State, Vols. i, ii in one, with an 

 atlas in a separate volume, 1880, and Vol. iii, text and plates, 1884, was 

 the fruit of his more or less continuous connection with the State Survey 

 from 1875. He regarded it as the crowning labor of his life, and resumed 

 into it all his knowledge of the flora of our coal measures. Another vol- 

 ume, in preparation at the time of his death, was intended to contain the 

 figures and descriptions of about a hundred new species, some of them of 

 exceptional beauty and interest ; and many of which were founded on 

 specimens in the rich private collection of his most intimate friend and 

 fellow-worker, Mr. R. D. Lacoe, of Pittston, Pa., who looked much after 

 the old man's comfort, and frequently entertained him as his guest for 

 days and weeks' together, most of the time being spent in examining, com- 

 paring and discussing doubtful species and new discoveries. 



For his comparisons of foreign species, his three principal correspond- 

 ents were Schimper of Strasburg, Heer of Zurich, and Count Saporta. 

 Schimper was one of his earliest intimates in botany and he was never 

 willing to consider a question settled until after letter after letter had 

 passed between them. His American studies of the Cretaceous and Ter- 

 tiary floras of America supplied copious and constant food for botanical 

 correspondence with Heer. 



In the earlier years of his residence in the State of Ohio he was em- 

 ployed by Mr. W. S. Sullivant, a wealthy citizen of Cincinnati, a bryolo- 

 gist given to the study of mosses, and assisted him in the publication of* 

 many new species. This brought him into intimate correspondence with 

 the well-known bryologist of Philadelphia, Mr. Thomas P. James, a mem- 

 ber and officer of this Society. After Mr. James left Philadelphia to 

 reside in Cambridge, Mass.,. Mr. Lesquereux's botanical intercourse 

 with him was constant and fruitful, and much of the value of the 

 "Manual of the Mosses of N. America," published in their respective 

 names, was due to the zeal with which he thus kept alive those earliest 

 studies of his life. Another of his closest friends was the veteran profes- 

 sor of botany at Lafayette College, Easton, Pa., Thomas C. Porter, who 

 has some amusing anecdotes to tell of their adventures among the rare 

 plants surviving on the banks of the Delaware. 



Lesquereux was elected a member of this Society January 18, 1861, and 

 of the National Academy of Sciences in 1864, the year following its const! 



