662 The American Naturalist. [July, 
shape from those of the former species. Found by R. A. Stevenson 
in the upper beds. 
Blastomeryx antilopinus sp. nov.—8Size decidedly smaller than that of 
B. borealis Cope, and ribs of external crescents on upper molars less 
prominent. Found by O. C. Mortson in the upper beds. 
Besides the new forms here enumerated excellent materials were 
found of species already named, including some nearly complete skele- 
tons, which will be fully described in the memoir now in preparation. 
. Scorr 
Geological Museum, Princeton, N. J., June 9,1893. 
Conditions of Erosion beneath Deep Glaciers.—Mr. N. S. 
Shaler has published a paper on the conditions of Erosion beneath deep 
glaciers, based upon a study of the Boulder Train from Iron Hill, 
Cumberland, R. I. The author advances an hypothesis of pressure 
melting to account for unexplained peculiarities of glacial movement, 
such as sudden variations of a temporary nature in the position of the 
ice, and the movement of the ice in the direction of the glacial flow over 
surfaces of slight inclination. It also accounts for the small amount of 
erosion often traceable in the central parts of a glaciated district, and 
explains the phenomena exhibited by drumlins or lenticular hills. 
(Bull. Harv. Mus. Comp. Zool., Vol. XVI, 1893.) 
Paleozoic.—Mr. Whiteaves has published a list of 16 gasteropods 
found in the Trenton limestone of Manitoba, of which, one Loxonema 
winnipegense, is new. The new species is of interest on account of its 
close similarity to some of the most typical Jurassic species of Pseudo- 
melania. (Can. Rec. Sci. April, 1893)—A new fungus, Jncolaria 
securiformis, is reported by Mr. H. Herzer. It was found under the 
bark of a Sigillaria imbedded in the Zoar limestone of Tuscarawas Co., 
Ohio and represents a new genus: (Am. Geol. June, 1893). A new 
fern from the Coal Measures of Henry Co., Missouri, is described and 
figured by Mr. David White in the Bull. Geol. Soc. Amer., 1893 under 
then name —M irina; According to the author the new 
of tæniopteroid and alethopteroid 
eo 
eharkoters. 
Mesozoic.—Mr. N. H. Darton has defined a thin series of arenace- 
deposits lying t between the Potomae and Severn formations, to which . 
i y formation. Its stratigraphic position places 
poe Cretaceous. (Ann. Journ. Sci. 1893). Mr..P. B. Brodie 
