^ AMEBICA. 135 



Bridger and Green River groups. Beds of lignite occur throughout the 

 Cretaceous of S. and S.E. Colorado, and also in Utah and Wyoming. 

 The upper part of the Cretaceous overlaps the lower. A few strati- 

 graphical details are given. W. H. D. 



Hayden, Dr. P. V. The Grotto Geyser of the Yellowstone National 

 Park. {U. S. Geol, Surv, Terr,) Fol. Pp. 6 ; 2 plates (view and 

 map). 



Account of the Geyser, with analysis of its deposits, by Dr. A. C . 

 Peale. 



. Note on the ore-bearing rocks of Colorado. Amer. Journ, 



ser. 3, vol. xii. p. 71. 



Corrects the statement in Ann. Rep. U. S. Geol. Surv. Territories for 

 1874, p. 4, that the Archaean rocks alone are ore-bearing in Colorado. 

 Silurian (?) and volcanic rocks are ore-bearing in some parts. G. A. L. 



Hitchcock, Prof. C. H. Atlantic System of Mountains. Appalachian 



vol. i. no. 1. 



Holmes, Judge — . Man and the Elephant in Nebraska. Proc. Ac, 



Sci. St. Louis, vol. iii. pp. ccxiii, ccxiv. 

 Argues that the discoveries of Dr. S. Aughey in Nebraska " are not 

 open to the same kind of explanation [as those of Dr. Koch], and seem 

 to afford the necessary confirmation of the supposed contemporaneity 

 of man and the mastodon and elephant in this [the Missouri] valley." 



G. A. L. 



Holmes, W. H. A Notice of the Ancient Ruins of South-western 

 Colorado, examined during the Summer of 1875. Bull. U. 8. Geol, 

 Surv. Territories, vol. ii. p. 1. 



Plate 6 has a geological section of the canon- wall. 



Howell, Edwin E. Report on the Geology of portions of our Western 

 Territory visited in the years 1872 and 1873. Pp.70. 4to. Wash- 

 ington. 



Hunt, Dr. T. S. The Quebec Group in GeologyT Proc. Boston Soc, 

 Nat. Hist. vol. xix. pp. 2-4, abstract. 



The name " Quebec Group " given by Logan is misleading, as it 

 includes several unconformable groups — Laurentian, Cambrian, and L. 

 saurian. W. H. D. 



Irving, Roland. Note " On the youngest Huronian rocks South of 



Lake Superior.*' Amer. Jouim. ser. 3, vol. xi. p. 493. 

 Corrects a statement by T. B. Brooks (see p. 129). 



Jackson, James. Explorations faitea sous la direction du Docteur 

 F. V. Hayden pendant I'annee 1875 dans les territoires de TOuost 

 des £tats Unis. [Resume of Hayden's Surveys in 1875.] Bull, 

 Soc, Geogr. Paris, 6 ser. t. xii. pp. 196-199. 



