— 76 — 
He came to Boston, and became an inmate of the Agassiz household, 
working on the botanical part of Agassiz’s “ Journey to Lake Superior” until 
Christmas Eve., 1848, when at the invitation of William Starling Sullivant he 
went to Columbus, Ohio, and, entering that eminent bryologist’s laboratory, 
continued the study of mosses. , 
At the close of the year 1849, under the advice and with the co-operation 
of Mr. Sullivant. he made a tour of exploration among the mountains 
of the Southern States, for the collection of plant specimens, and 
secured a great variety of plants, which found a ready sale among 
scientific students. He was particularly successful in the collection 
of mosses. The preparation of the specimens, their determination and 
distribution, gave him employment for two years, and resulted in one of the 
most valuable contributions to American bryology — the “ Musci Americani 
Exsiccati,” by W. S. Sullivant and L. Lesquereux. The expense of prepa- 
ration and publication of this work was defrayed by Mr. Sullivant, who 
allowed his colleague the benefit of the sales. Using that author’s library 
and herbarium — now the property of Harvard College — for their common 
studies, Lesquereux lent most valuable assistance to the preparation of Mr. 
Sullivant’s works on the mosses of the Wilkes’ South Pacific Exploring 
Expedition, Whipple’s Pacific Railroad Exploration, and the “leones Mus- 
corum.” The publication of Brongniart’s “ Prodrome,” and the commence- 
ment of the “ Histoire des Vegetaux Fossils,” in 1828, laid the solid basis 
upon which the science of paleobotany has been erected. Lesquereux began 
to write in 1845, and his studies in America have been directed especially in 
the line of fossil botany. His most valuable researches, beginning in 1850, 
lay in the study of coal formations of Ohio, Pennsylvania, Illinois, Ken- 
tucky, and Arkansas, and his reports appear in the geological surveys of 
all these States. Particularly important are his studies of the coal flora of 
Pennsylvania, published in the report of H. D. Rogers in 1858, together with 
a “ Catalogue of the Fossil Plants which have been named or described from 
the Coal-Measures of North America.” Lesquereux also worked up the coal 
flora in the second geological survey of Pennsylvania. The fruit of this 
labor was two volumes of text and an atlas, published in 1880 — -the most im- 
portant work on carboniferous plants that has been produced in America. 
Geological work, especially researches on fossil botany, in connection with 
the United States Geological Surveys of the Territories, began in 1868 to 
absorb his attention. He was employed to work up the collection of -Dr. F. 
V. Hayden’s surveys of the Territories, and important papers on the subject 
appeared in the annual reports of the surveys from 1870 to 1874 inclu- 
sive. Lesquereux was frequently called to Cambridge to determine the 
specimens of fossil plants in Professor Agassiz’s museum, where he was a 
guest in the naturalist’s household for weeks and months at a time, and his 
attachment to him grew very strong. 
The fraternal bond that binds the scientific world is very strong as was 
witnessed by his attachment to Guyot and Agassiz, the former coming to this 
country at the same time as Lesquereux, and both only two years after 
Agassiz arrived. 
