34 
107 Cross (Whitman). The laccolitic mountain groups of Colorado, 
Utah, and Arizona. 
U. S. Geol. Surv., 14th Ann. Rept., pt. 2, pp. 165-241, pis. vii-xvi, tigs. 
25-43. 
Reviews the literature of the laccolitic theory. Describes the lac- 
colites of the Henry, West Elk, San Miguel, La Plata, Carriso, El Late, 
Abajo, and La Sal mountains, Mosquito range, and the intrusive rocks 
of the Ten Mile district, Colorado. Discusses the chemical and min- 
eralogic characters of laccolitic rocks, the conditions under which they 
were formed, and the forms and origin of laccolites. 
108 Pikes Peak folio. Colorado. 
U. S. Geol. Surv., Geologic Atlas of the United States, folio 7. 
Describes the topographic features, the granite and metamorphic 
rocks, the occurrence and distribution of the Algonkian, Cambrian, 
Silurian, Carboniferous, Juratrias, Cretaceous, and Eocene strata. 
Describes the occurrence and petrographic characters of diabase, sye- 
nite, andesite, rhyolite, trachyte, phonolite, and the geographic distri- 
bution of the sedimentary and igneous formations and the structural 
development of the region. Includes a topographic, colored areal 
geologic, economic geologic, and structure section maps. 
109 Description of the igneous formations [Anthracite-Crested 
Butte folio, Colorado]. 
U. S. Geol. Surv., Geologic Atlas of the United States, folio 9. 
Describes the character and occurrence of diorite, porphyrite, por- 
phyritic diorite, granite, rhyolite, and basalt, in the portion of Colo- 
rado included within the district named. 
110 Intrusive sandstone dikes in granite. 
Geol. Soc. Am., Bull., vol. v, pp. 225-230, pi. 8. 
Abstracts : Am. Jour. Sci., 3d ser., vol. xlvii, p. 142 (7 1.); Am. Geol., 
vol. xiii, p. 215 (8 1.); Am. Nat., vol. xxviii, pp. 412-413. 
Describes the portion of Colorado in which the dikes occur, their 
characteristics and mode of occurrence. Describes the dike rock and 
discusses the origin of dikes. 
111 Itinerary, Nathrop to Salida, Colo. 
Int. Cong. Geol., Compte Rendu, 5th session, pp. 423-424. 
Describes the geology along the railroad between these points. 
112 Manitou. Itinerary, Colorado Springs to Denver. Excursion 
to Morrison. Excursion to Golden [Colo.]. 
Int. Cong. Geol., Compte Rendu, 5th session, pp. 430-442. 
Describes tne geology of the Pikes Peak region, the geology of the 
Denver Basin, and the character of the Juratrias and Cretaceous beds 
at Morrison and Golden, Colo. 
113 Cubberly (E. P.). Indiana's structural features as revealed by 
the drill. 
Ind. Dept. Geol. and Nat. Res., 18th Rept., pp. 219-255, with map 
and 16 colored geologic sections. 
Each geologic section is accompanied by a table showing the depth 
of the well, the formations penetrated, and other data on which the 
sections are based. 
