1893.] NATURAL SCIENCES OF PHILADELPHIA. 347 



Penrose, R. A. F., Jr. — A Preliminary Report on the Geol- 

 ogy of the Gulf Tertiary of Texas, etc. First Ann. Rept., Geol. 

 Survey Texas, 1889, pp. 5-101. 



Penrose, R. A. F., Jr. and Hill, R. T.— Relation of the 

 Uppermost Cretaceous Beds of the Eastern and Southern United 

 States. Am. Journ. Sci., XXXVIII, Dec, 1891, pp. 468-73. 



Shumard, Geo. G. — A Partial Report on the Geology of Western 

 Texas, Austin, Texas, 1886, 145 pp. 



Taff, J. A. — Cretaceous Deposits of Trans-Pecos Texas. Second 

 Ann. Rept., Geol. Survey Texas, 1890, pp. 714-738. 



Tarr, R. S. — Origin of Some of the Topographic Features 

 of Central Texas. Am. Journ. Sci., XXXIX, pp. 306-311. 



Tarr, R. S. — A Preliminary Report on the Coal Fields of 

 the Colorado River. First Ann. Rept., Texas Geol. Survey, 1889, 

 pp. 201-216. 



Tarr, R. S. — The Carboniferous Area of Central Texas. Am. 

 Geol, Vol. VI, 1890, pp. 145-153. 



Tarr, R. S. — Superimposition of the Drainage in Central Texas. 

 Am. Journ. Sci., XL, 1890, pp. 359-62. 



Tarr, R. S. — The Permian of Texas. Am. Journ. Sci., XLIII, 

 1892, pp. 9-12. 



Tarr, R. S.' — The Cretaceous Covering of the Texas Palaeo- 

 zoic. Am. Geol., Vol. IX, 1892, pp. 169-178. 



Tarr, R. S. — A Hint with respect to the origiu of Terraces in 

 Glaciated Regions. Am. Journ. Sci. XLIV, 1892, pp. 59-61. 



Tarr, R. S. — Reconnoissance of the Guadalupe Mountains. Bull. 

 3, Texas Geol. Survey, 1892. 



Walcott, C. D. — Discussion. — Bull. Geol. Soc. Am., Vol. II, 

 1891, pp. 526-7. 



