278 University of California Publications. [Geology 



a summary of a vast amount of observational detail bearing on 

 the general problems of his paper. The charts showing maxi- 

 mum and minimum surface temperatures will first be examined. 

 These were prepared by laying off on 2° squares all the recorded 

 observations of surface temperatures. The tables of Admiral 

 Makaroff give 38,874 observations for the North Pacific. Murray 

 has supplemented these by the reports of the British Admiralty 

 Office and from other sources. The maximum and minimum 

 temperatures are taken for the months of August and February 

 respectively. Nearly 25% of the 2° squares in the North Pacific 

 have no recorded observations. This lack should be borne in 

 mind, but as nearly half of these omissions are in the Torrid 

 Zone, it is not likely that the mapping of maximum or August 

 temperatures in the broad belt of these charts has been seriously 

 affected. 



Maximum Surface Temperatures. — PI. 34 B shows the results 

 for the North Pacific, the temperature zones indicating difference 

 of 10° F. So far as the problems of this paper are concerned, the 

 most marked departure from east and west boundaries to these 

 zones is found in the belt of 60°-70°. This shows a notable ex- 

 tension southward along the coast of the United States and re- 

 veals the belt of cold coast water, confirming the existence of a 

 southward flowing drift off the coast, as shown on the Pilot 

 Charts. The torrid belt of 80°-90° makes a northward extension 

 along the coast of Lower California. This again confirms the 

 Pilot Chart which shows a northwestward flowing current off 

 the Mexican coast. 



Minimum Surface Temperatures. — PL 35 A is the chart for 

 minimum surface temperatures in the North Pacific. Here again 

 is the southward extension of the cold belt along the western coast 

 of North America. An interesting fact here is the bend to the 

 southward along the 120th meridian showing that the currents 

 from the north leave the shores of America turning to the west- 

 ward. 



Range of Surface Temperatures. — PL 35 B is from another 



chart by Mu rray from the same data.* The annual range of tem- 



* Murray, Sir John. Annual Range of Temperature, etc. Geog. Jour. 

 1898, Vol. XII, p. 113. 



