NOV. 19, 1921 



ABSTRACTS : PALEONTOLOGY 



471 



fore have existed at the time the salt was deposited. The greatest thick- 

 ness reported is 700 feet. Thicknesses of 200 to 400 feet are not uncommon. 

 For several years commercial deposits of potash salts have been sought 

 in this salt mass but so far without success. Verbal records and graphic 

 logs of the principal wells penetrating the salt in this area are given for each 

 State involved. The author believes that the salt was formed by the evapora- 

 tion of sea water in shallow basins with occasional deeper marine submer- 

 gences indicated by beds of [marine?] limestone. 



Marcus I. Goldman. 



GEOGRAPHY and HYDROLOGY .—Routes to desert watering places in the 

 Salton Sea region, California. John S. Brown. U. S. Geol. Survey 

 Water-Supply Paper 490-A. Pp. SG, pis. 7, figs. 2. 1920. 

 .This is the first of a series of detailed guidebooks on watering places in 

 the desert region of the United States that is being prepared by the U. S. 

 Geological Survey as authorized by Congress. The text comprises a brief 

 description of the Salton Sea region — about 10,000 square miles in extent — 

 practical suggestions to travelers, detailed logs of all desert roads with special 

 reference to water supplies, and a list of watering places with brief descrip- 

 tions. There is also a preface by O. E. Meinzer, which outlines the desert 

 region of the United States (about 500,000 square miles in extent) and de- 

 scribes the scope and methods of the watering-place survey. The maps 

 include a general map of the desert region of the United States and detailed 

 relief maps of the Salton Sea region showing roads and watering places. 

 The relief shading is by John H. RenshawE- O. E. M. 



PALEONTOLOGY.— Orthaulax, a Tertiary guide fossil. C. Wythe Cooke. 



U. S. Geol. Survey Prof. Paper 129-B. Pp. 15 (23-37), pis. 4 (2-5). 1921. 



Had this paper been written even so late as five years ago, it might well 



have been entitled, "Orthaulax, a guide fossil of the Middle Oligocene." 



The more conservative caption is necessitated by recent discoveries in Santo 



1 slraligraphic occurrence of OrOumUtx. 



• FmuwI vvldeDce 



vtdmce U iwcumul^ilDi. Kcordlog to T. W. V«ush«D, tbsi tbsM lormatlons cIbsmI by him in Drcrious t«porti as TortonUa (uppfrr Miocene), ar« ol IlelwtiKD (middle Uioccne) i>i;«. Thli is 

 cplnlon suted by DtJlla IMH. 



