-Manrcu 8, 1901.] 
of the hanging lateral valleys are results of 
glacial erosion. He concludes that the lateral 
valleys are the remains of an ancient topog- 
raphy in which the trunk and the branch val- 
leys were accordant; that the lateral valleys, 
long occupied by uévé and ice, have been 
preserved from erosion, while the trunk val- 
ley has been deepened chiefly by stream ac- 
tion during interglacial and postglacial epochs. 
Overdeepened valleys when thus interpreted 
are witnesses rather to the conservative action 
of glaciers than to their destructive action 
(Note sur le surcreusement (‘ Uebertiefung’) 
des vallées alpines. C. R. Soc. géol. France. 
Dec. 17, 1900, 160-162). W. M. Davis. 
BOTANICAL NOTES. 
ELLIOTT’S GRASSES. 
THOSE who are fortunate enough to possess a 
copy of Stephen Elliott’s rare two-volume 
work entitled ‘A Sketch of the Botany of South 
Carolia and Georgia’ will be glad to know 
that Professor Scribner, of the Division of 
Agrostology of the United States Department 
of Agriculture, has published a circular (No. 
29) giving the results, so far as the grasses are 
concerned, of a critical examination of Elliott’s 
Herbarium, now in the possession of the Col- 
lege of Charleston, South Carolina. He has 
been able in this way to verify E!liott’s deter- 
minations, and to make necessary corrections, 
the latter due to the fact that in many cases the 
species had been named previously by foreign 
botanists, and, also, that many changes in 
nomenclature have occurred in the eighty or 
more years which have elapsed since the publi- 
cation of Elliott’s ‘sketch.’ This herbarium is 
said to consist of twenty-eight volumes of folios, 
twelve by twenty-three inches in size, and that 
part containing the grasses is described as ina 
‘very good state of preservation.’ It is curious 
that in working over the species, the author 
(who was assisted by Mr. HK. D. Merrill) found 
it necessary to deseribe two or more species, 
viz., Panicum amaroides (to be separated from 
Elliott’s P. amarum, and hitherto known as P. 
amarum minor Vasey), and Panicum=subbarbula- 
tum (the P. barbulatum of Elliott, but not the 
P. barbulatum of Michaux). 
SCIENCE. 
397 
WOOD’S HOLL BOTANY. 
THE announcement of the botanical work of 
the fourteenth season (1901) of the Marine 
Biological Laboratory, of Wood’s Holl, Mass., 
has just been received. Dr. Bradley Moore 
Davis, of the University of Chicago, will be in 
charge again, as he has been for several years 
past. The session opens July 3d, and extends 
to August 14th. Work is offered along four 
lines, viz.: Cryptogamic Botany (algae or fungi, 
or both); Phanerogamic Botany (the outdoor 
study of flowering plants; Plant Physiology 
(experiments and lectures); and Plant Cytology 
(a laboratory course in methods). Lectures by 
specialists will be provided as in previous 
years. A special welcome will be accorded to 
investigators who desire to carry out special 
lines of research. Announcements giving fur- 
ther details may be obtained of Dr. Davis. 
NEW SPECIES OF NORTH AMERICAN TREES. 
Ir will surprise many readers to learn that 
critical botanists have recently discovered many 
hitherto undeseribed species of North American 
trees. In the January number of the Botanical 
Gazette, Professor ©. S. Sargent discusses ‘ New 
and Little Known North American Trees,’ in 
which he describes seven new species, viz.: 
Gleditsia tevana (a tree one hundred to one hun- 
dred and twenty-five feet high, and two and a 
half feet in diameter, from the valley of the 
Brazos river, Texas) ; Crataegus engelmanni (fif- 
teen to twenty feet high, and closely related to 
0. crus-galli, from Missouri to Alabama); Cra- 
taegus canbyi (twenty to twenty-five feet high, 
also related to C. crus-galli, from Delaware) ; 
Crataegus peoriensis (twenty to twenty-five feet 
high, from central Illinois); Crataegus pratensis 
(a small tree from central Illinois) ; Crataegus 
submollis (a large tree hitherto confounded with 
C. mollis, from Maine to Montreal and Massa- 
chusetts) ; Crataegus dilatata (a small tree re- 
lated to C. coceinea, from Vermont, Massachu- 
setts and. Rhode Island); Crataegus coccinea 
rotundifolia (the C. rotundifolia of Moench, one 
of the commonest of New England forms) ; and 
Crataegus jonesae (a small tree closely related 
to C. coccinea, from southeastern Maine). 
Ashe’s species, C. holmesiana, from Quebec and 
Ontario to Maine, Massachusetts, New York 
