1894.] MICROSCOPICAL JOURNAL. 175 



In the Bulletin of tlie department of Geology of the 

 University of California, 1893, is an article by Prof. 

 Andrew C. Lawson on the geology of Carmelo Bay in 

 California, wherein he speaks of the Monterey series, 

 meaning the light colored rocks which contain the Dia- 

 tomaceae and which I have spoken of as found on the 

 Pacific coast of California. He gives the results of a 

 chemical analysis as follows : 



Silicic oxide 86.89 



Aluminum oxide ... 2.32 



Ferric oxide 1.28 



Calcium oxide 0.43 



Magnesium oxide trace 



Potassium oxide 1.2G 



Sodium oxide 2.32 



Iguitiou 4.89 



99.39 

 But this immediate specimen contained no Diatoma- 

 ceous remains, and it is interesting to remark that Prof. 

 Lawson, although classifying the rocks as Miocene, says : 

 " The infusorial beds at Monterey appear, therefore, to be 

 exceptional and not representative of the series as a 

 whole," and it is suggested that perhaps the microscopic 

 examination of the Monterey shale will show , as the ge- 

 ological analysis shows, it to be of volcanic origin — show- 

 ing that we do not understand the geology of these 

 rocks. 



To Mount Certain Salts. 



By NO SIG. 



PARIS. 



NITRATE OF URANIUM. 



This is a most difficult salt to mount after having ob- 

 tained a faA^orable specimen of crystalization, and requires 

 the greatest attention to the most minute details in 

 order to succeed in producing a satisfactory, well fin- 

 ished slide. A solution should be made nearly satu- 

 rated and filtered. 



