394 The American Geologist. June, 1895 
The same, vol. xvi (Greol. Ser.. vol. n), no. 15; Notes on the geology 
of the island of Cuba, R. T. Hill. Pp. 248-288, pis. 1-9, April, 1895. 
Bull. Univ. of Wisconsin, science series, vol. 1, no. 2: On the quartz 
keratophyre and associated rocl\S of the north range of the Baraboo 
bluffs, Samuel Weidman. Pp. 35-50, pis. 1-3, Jan., 1895. 
Colorado College Studies, 1894, contains: The origin and use of the 
natural gas at Manitou, Colorado, Wm. Strieby; The Choctaw and 
Grayson terranes of the Arietina, F. W. Cragin; Descriptions of new 
species of Invertebrata from tlie Comanche series in Texas, Indian Ter- 
ritory and Kansas, with definition of two Comanche terranes, F. W. 
Cragin; Yertebrata from the Neocomian of Kansas, F. W. Cragin. 
Kansas Univ. Quarterly, vol. iii, no. 4, April, 1895, contains: Semi- 
arid Kansas, S. W. Williston; The stratigraphy of the Kansas Coal 
Measures, Erasmus Haworth; Division of the Kansas Coal Measures 
Erasmus Haworth; the coal fields of Kansas, Erasmus Haworth. 
CORRESPONDENCE. 
A CoRKECTiON. In the writer's recent papers entitled "The Second 
Lake Algonquin" (American Geologist, Feb. and March, 1895), and 
"Niagara and the Great Lakes" (Am. Jour. Sci., April, 1895), the name 
"Erigan" was adopted from Prof. J. W. Spencer's writings and used as 
the name of a section of the Niagara gorge and of tlie river wliicli made 
that section. This course was adopted with the best of intentions. It 
was supposed that it would be the closest po.ssible conformity to previ- 
ous use. But it is learned by a recent letter from Prof. Spencer that the 
writer's use of the name Erigan is entirely different from his. The mis- 
take would probably not have occurred, but for an unfortunate combi- 
nation gf circumstances, including the loss of a reprint in which Prof. 
Spencer originally used the name, and also the absence of Prof. Spencer 
in Jamaica and southern Mexico and tlie consequent failure of the 
writer to get an answer to a letter of inipiiry addressed to him early in 
the winter. For these reasons the writer was led to rely solely upon his 
memory. Prof. Spencer's Erigan river, like that so named by the 
writer, drained only lake Erie. But it was entirely pre-Glacial and it 
followed the Grand River vallej- northward to the Dundas valley at the 
west end of lake Ontario and lience did not occupy the Niagara channel 
at all. (See "Origin of the Basins of the Great Lakes of America" by 
J. W. Spencer. Quart. Jour. Geol. Soc, Nov., 1890, map page 2.) In 
the writer's articles referred to above the use of the name Erigan is 
confined in the first to pages 167 to 179, and in the second to pages 26G 
to 270. In place of that name it is proposed to substitute the name 
"Little Niagara." This will be the name of the river which made the 
narrow, shallow gorge of the "Whirlpool rapids, and that part of the 
gorge may be called the Little Niagara gorge. It is believed that the 
