838 THE POPULAR SCIENCE MONTHLY. 



the close of the year 1849, under the advice and with the co-cperation 

 of Mr. Sullivant, he made a tour of exploration among the mountains 

 of the Southern States, for the collection of plant-specimens, and se- 

 cured a great variety of plants, which found a ready sale among sci- 

 entific 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 preparation 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 as- 

 sistance to the preparation of Mr. Sullivant's works on the mosses of the 

 AVilkes' South Pacific Exploring Expedition, Whipple's Pacific Rail- 

 road Exploration, and the " Icones Muscorum." The publication of 

 Brongniart's " Prodrome," and the commencement 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 the coal formations of Ohio, Pennsylvania, Illinois, 

 Kentucky, and Arkansas, and his reports appear in the geological sur- 

 veys 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 sur- 

 vey of Pennsylvania. The fruit of this labor was two volumes of text 

 and an atlas, published in 1880 — the most important work on carbon- 

 iferous 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 collections 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 

 inclusive. Lesquereux was frequently called to Cambridge to deter- 

 mine 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. 



Lesquereux, during his long and industrious life, has contributed 

 twelve important works to the natural history of North America, 

 besides a large number of memoirs on divers subjects, amounting in 

 all to about fifty publications. He is a member or correspondent of 

 more than twenty scientific societies of Europe and America, and was 

 the first elected member of the National Academy of Sciences. The 



