580 The American Naturalist. [June, 
Jain down during the presence of the ice. Afterwards a decreased 
volume and a rising land will account for the rest of the work done in 
postglacial times. In other words, the upper terrace plain is due to a 
glacial accident in the river’s history, and the upper escarpment was 
formed as the river cut down toward base-level after the land rose when 
relieved from the weight of ice. The later terraces formed asthe river 
sank its channel deeper into the glacial waste, each terrace plain repre- 
senting the temporary level of the stream, and each escarpment show- 
ing intermittently rising land. (Proceeds. Boston, Soc. Nat. Hist., 
Vol. XXVI, 1894.) 
A fossil mandible in the Museum at Brisbane, Queensland, is referred 
by Mr. De Vis to Zygomaturus. In commenting on the supposed 
identity of this genus with Nototherium Owen, the author says that 
this mandible shows the two genera to be distinct and that Zygomaturus, 
and its three allies, Diprotodon, Nototherium, and Euowenia, form 
a natural family of the phascolomine section of the marsupials. (Proc. 
Roy. Soc. Queensland, Vol. XI, 1895.) 
BOTANY. 
Progress of the Botanical Survey of Nebraska.—From data 
recently obtained the following statement is made of the progress of 
the Botanical Survey of Nebraska. From its beginning, several years 
ago, the Survey has been a private enterprise, supported and encour- 
aged by the University of Nebraska, the State Board of Agriculture, 
and the State Horticultural Society. The immediate work is in the 
hands of the Botanical Seminar, an organization of graduates of the 
botanical department of the University of Nebraska. Through the 
energy of the members of the Seminar expeditions have been made 
from time to time to nearly all parts of the State, and in some cases 
these have been of extended duration. The first considerable publica- 
tion was made in 1890 when H. J. Webber’s “ Catalogue of the Flora 
of Nebraska” appeared in the Report of the State Board of Agricul- 
ture. Reprints of this catalogue were issued under separate cover, and 
these have formed the basis of subsequent work and publication. This 
catalogue, unlike many local publications of its kind, was based upon 
1 Edited by Prof. C. E. Bessey, University of Nebraska, Lincoln, Nebraska. 
