weeks] PALEONTOLOGY, PETROLOGY, AND MINERALOGY, 1894 49 
228 Gresley (W. S.). The "slate binders" of the "Pittsburg" coal 
bed. 
Aiu. Geol., vol. xiv, pp. 356-365, figs. 1-2. 
Describes the character of the slate partings and discusses the dif- 
ferent theories which may account for the formation of similar beds. 
229 Grimsley (G. Perry). The granites of Cecil County, in northeast- 
ern Maryland. 
Cin. Soc. Nat. Hist., Jour., vol. xvii, pp. 59-67, pis. 4-5, and pp. 78-114. 
Abstracts: Jour, of Geol., vol. ii, pp. 865-866; Am. Geol., vol. xiv, 
p. 398 (i p). 
Describes the rock exposures and the microscopic characters of the 
granite, diorite, staurolitic mica-schist, and granite-gneiss found in 
this region. Gives a summary of conclusions. 
229a Griswold (L. S.), Davis ( W. M.) and. Eastern boundary of the 
Connecticut Triassic. 
Geol Soc. Am., Bull., vol. v, pp. 515-530. 
See Davis (W. M.) and Griswold (L. S.), No. 139. 
229^ Gulliver (F. P.). Ice sheet on Newtonville sand plain. 
Abstract: Am. Assoc. Adv. Sci., Proc, vol. xlii, p. 178 (£ p.) 
Noticed in Bibliography and Index for 1892 and 1893. 
230 Gurlt (Adolf). On a remarkable deposit of wolfram ore in the 
United States. 
Am. Inst. Mg. Engrs., Trans., vol. xxii, pp. 236-242. 
Describes an occurrence of wolfram ore in Fairfield County, Conn., 
in crystalline limestone and gneiss. 
231 Hague (Arnold). The great plains of the North. General sketch. 
Itinerary from Jamestown, 1ST. Dak., to Livingston, Mont. 
Int. Cong. Geol., Compte Rendu, 5th session, pp. 319-325. 
Describes the general geologic features of the great plains and the 
local geology of the route traversed by the Rocky Mountain excursion 
of the International Congress of Geologists. 
232 The Yellowstone Park. 
Int. Cong. Geol., Compte Rendu, 5th session, pp. 336-359. 
Describes the geologic history of the park and the physical and 
geologic features of the route through the park traversed by the 
excursion. 
232a Geologic history of the Yellowstone National Park. 
Smitb. Inst., Ann. Rept., 1891-92, pp. 133-151. 
Noticed in Record of North American Geology for 1887-1889. 
233 Hall (James). The Livonia salt shaft; its history and geological 
relations, etc. 
N. Y. State Mus., 47th Ann. Rept., pp. 205-214. 
Gives an account of the geologic- work done during the sinking of 
tho Livonia shaft and describes the relations of the formations. 
Bull. 135 4 
