yi Sphinctozoan Cdlcispomjc. — Clurke. 387 
Elsewliere the evidences of readvances of the iee-sheet in 
our Atlantic coastal region, alforded by fossiliferous beds un- 
derlain and overlain b}'' glacial deposits, as observed by the 
present writer in southeastern New Hampshire,* by Prof. C. 
H. Hitchcock at Portland. Maine.f and by Mr. Robert Chal- 
mers near St. John, N. B.,+ appear to indicate only moderate 
fluctuations of the border of the continental ice-sheet. Nowhere 
east of the Ohio is a great glacial readvance demonstrated 
by plentiful fossiliferous interglacial deposits and an old 
land siii-face, like those of the forest bed next underlying the 
lowan till in the upper part of the Mississippi basin. 
A SPHINCTOZOAN CALCISPONGE FROM THE 
UPPER CARBONIFEROUS OF EAST 
ERN NEBRASKA. 
Hy John M. Clarke, Albany, N. Y. 
(Plate XXIII.) 
In the prosecution of investigations upon the Carboniferous 
and Permian formations of Nebraska and Kansas, § professor 
Charles S. Prosser, of Union College, Scheneetad3% N. Y.. col- 
lected a series of interesting specimens of a calcisponge wiiicli 
he has kindly given rae the opportunity of studying. As these 
))rove to represent a group of sponges not before observed in 
American fossil faunas, they are entitled to brief notice. Tlie 
geologic position of these bodies is the Wabaunsee formation 
(Prosser), the middle division of the upper Carboniferous, at 
the villages of Nehawka and Weeping Water, Nebraska, where 
they are associated with well known species, such as: SemiU' 
ula subtilitAi, Derbtja cras.sa, Enteletes hemiplicalu, Chonetes 
firanulifera, Productns l<>t}(jispi)ius. IJasfedia mormoitt, Spiri- 
fer carneratus, S. lineatus, etc., etc. 
These specimens represent a species of the annulated and 
chambered calcisponges wliich have been found at various 
])laces in the upper Carboniferous and Mesozoic formations of 
Europe and Asia. Many of them bear a striking resemblance, 
*Geology of N. H., vol. iii, 1878, p. 163. 
tProu. A. A. A. S., vol. xxii, for 1873, pp. 1G3-175. Geology of N. ?!., 
vol. Ill, pp. 279-282. Geol. Maf?azine, II, vol. vi, 1879, pp. 248 250. 
tBullptin, G. S. A., vol. iv. 1892, pp. 361-370. 
v^See .Journal of Geology, vol v, no. 1 and 2. 1897. 
