138 
The paper consisted of an exhibition of 
lantern slides illustrating the peneplain of 
Brittany, and of its detached portions in 
Jersey and Belle Isle, as well as of certain 
valleys by which the peneplain has been dis- 
sected since its elevation ; and of comments 
in which the speaker argued that the plain 
was not one of marine denudation, but was 
subaérial. 
The paper led toa quite extended discus- 
sion of the criteria for plains of marine 
origin, chiefly emphasized by N.S. Shaler 
and H. M. Ami, and of those of subaerial 
character, as developed by C. D. Walcott 
and G. K. Gilbert. 
An Excursion to Colorado Canyon: W. M. 
Davis, Cambridge, Mass. 
Observations made in the canyon of the 
Colorado and over the plateaus on the 
north and south, during a three weeks’ trip 
in June, 1900, add the occurrence of cer- 
tain landslides and migrating divides to the 
evidence already stated by Dutton in favor 
of two cycles of erosion in the development 
of the Grand Canyon district; the broad 
denudation of the plateaus having been ac- 
complished in the first cycle, and the incision 
of the narrow canyons in the second. The 
faults by which the plateaus are divided 
are regarded as for the most part of greater 
antiquity than the canyon cycle ; the ante- 
cedent origin of all the branch streams of 
the Colorado in this district is questioned ; 
and the high level floor of the Toroweap 
valley is explained otherwise than by the 
failure of its former water supply through a 
change from a humid to an arid climate. 
G. K. Gilbert corroborated the probabil- 
ity of the speaker’s views from the evidence 
of neighboring systems of drainage, and C. 
D. Walcott spoke in the same vein. 
Fossiliferous Layers in the Calciferous of Dutch- 
ess County, N. Y.: W. B. Dwicur, 
Poughkeepsie, N. Y. 
The paper described some recent discov- 
SCIENCE. 
[N.S. Von. XIII. No. 317. 
eries of a Calciferous fauna, somewhat re- 
lated to the Fort Cassin fauna of Vermont. 
It seems to identify the Calciferous for the 
first time so far south. It contains 24 spe- 
cies, of which 9 are trilobites. 
C. D. Walcott remarked its resemblance 
to the fauna at Phillipsburg, Vt., and to 
another at Eureka, Nev. 
Glacial Phenomena in Eastern Ontario: F. 
B. Tayzor. 
The speaker described the results of his 
observations of the moraines and other 
glacial phenomena in the portion of On- 
tario lying between Georgian Bay and 
Lake Ontario. At least four moraines can 
be identified which he endeavored to trace 
out to a connection with those further 
south. He also described an old river 
channel near Guelph which had been pro- 
duced by a stream flowing against the front 
of the ice sheet. 
The paper was discussed by W. M. 
Davis and A. P. Coleman. The former 
emphasized the importance of accurate 
phraseology in the nomenclature of glacial 
forms, the latter corroborated the general 
conclusions of Mr. Taylor in respect to the 
local geology. 
Biserial Development in the Plates of the Arms 
of Crinoids: A. GRABAU, Troy, N. Y. 
By means of a series of diagrams the 
speaker showed how the arms of crinoids 
begin with a uniserial set of plates, and 
then by the development of a series of 
wedge-shaped plates gradually become bi- 
serial. 
The Atchison Deep Well, Kansas: 
wortH, Lawrence, Kansas. 
The paper was read in abstract by J. F. 
Kemp in the absence of the author. It 
described a recent deep well at Atcheson 
which revealed two workable coal-seams 
and which threw new light on the struc- 
tural relation of the Coal Measures and 
Lower Carboniferous strata in this section. 
E. Ha- 
