130 KANSAS ACADEMY OF SCIENCE. 
work of phytopaleontology in America, became interested in the subject about 
this time. As early as 1856 he had observed fossil leaves in the sandstone near 
New Ulm, Minn.* Again, in 1859, his name appeared as a champion of the Swiss 
scientist in the Heer-Newberry controversy; but it was not until 1868 that his 
first contribution to the paleontology of the group appeared. It was entitled 
‘¢On some Cretaceous Plants from Nebraska,’’* and discusses fifty-three species, 
forty of which are considered new forms. This paper, published the same year 
as that of Doctor Newberry, was the first of a series by the same author. The 
material collected on the various expeditions of Doctor Hayden, as well as that 
sent from Kansas by Professor Mudge, John Leconte, Charles Sternberg, and 
others, was described in these reports. 
In addition to this, Doctor Lesquereux himself visited the collecting grounds 
and secured a large number of specimens. He was in Kansas in 1873, and the 
next year visited both Kansas and Nebraska. The various species mentioned 
from time to time were figured in his ‘‘Cretaceous Flora,’’™ published in 1874. 
This was the most comprehensive report so far published. A short historical 
sketch is annexed, and the various phases of the Dakota group are discussed 
with a remarkable clearness and penetration. The views here first set forth are 
in general still accepted by American paleobotanists. As new material was col- 
lected, it was sent to Doctor Lesquereux for identification. This necessitated 
additional publications, and almost every year brought forth from his facile pen 
a contribution to paleobotanic literature. In 1876 he published an extended 
article, in which a number of new forms are described and figured. Other 
articles followed, and in 1883 he published his ‘‘ Cretaceous and Tertiary Flora,” 
containing nearly 300 pages, accompanied by fifty-nine plates, seventeen of which 
are devoted to Dakota plants.” This was the second of the three monumental 
works on this group by this eminent scientist. During these years many collect- 
ors had been at work. Judge E. P. West, Prof, B. F. Mudge, H. C. Towner, 
Charles Sternberg and others had made extensive collections, especially in Ells- 
worth county, Kansas, where the Dakota reaches its typical development. The 
leaves collected were sent to several American universities, notably Harvard, and 
even to Europe. The largest collections, however, were secured for the Univer- 
sity of Kansas and for the Smithsonian Institution. Practically all of these 
fossils were identified by Doctor Lesquereux, who continued to publish descrip- 
tions of the various new forms. 
About 1885 he began his final work, a monograph entitled ‘‘The Flora of the 
Dakota Group.’’ The manuscript of this work, containing about 500 written 
pages, and including descriptions of 350 species, was submitted to the publisher 
in February, 1888. Before it could be published, however, additional discoveries 
of leaves were made in Kansas and the specimens sent to Doctor Lesquereux for 
identification. Although in feeble health, he began the work with his charac- 
teristic enthusiasm. Finding much new material, he requested that his manu- 
script and plates be returned to him, in order that he might incorporate it in the 
monograph. In a short time he had identified and described 110 new forms, 
bringing the number of species in the Dakota up to 460. Before the figures were 
all drawn, however, Doctor Lesquereux died, October 25, 1889. The monograph, 
edited by Dr. F. H. Knowlton, was published in 1892.* 
33. Cret. Flora, p. 6. 34, Am. Jour. Sci., 46: 91-105. 
35. Rept. U. S. Geog. Surv. Terr., vol. VI. 
36. U.S. Geol. and Geog. Surv. Terr., Bull. No. 1, 2d ser., pp. 233-248, 
37. U.S. Geol. and Geog. Surv. Terr., vol. VII. 
38. U.S. Geol. Surv., Mon. No. 17. 
