32 THE AMERICAN MONTHLY [Feb 



To Split Selenite. — The method adopted by Professor 

 Gates for sectioning- animal cells has been applied for some 

 time to splitting- selenite plates. It consists in cementing 

 them to g-lass and splitting- off very thin pieces which are 

 afterwards released from the glass by heat or other sol- 

 vent of the cement. Take for example a flat piece of some- 

 thing- less than an inch square and for practice split it 

 down to a fortieth or a fiftieth of an inch in thinness. 

 Glue or even mucilag-e will dofor the cement, Withafine, 

 thin and sharp blade detach as many layers as possible till 

 at last you leave an extremely thin slice attached to the 

 g-lass. Detach with warm water or other solvent of the 

 cement. Cement other pieces to the g-lass ad libitim. The 

 Nichols prism and crystalline objects will answer to test 

 the proper thickness or thinness reached. 



To Mount Pollen. — Digest in a warm pla^e, in a well 

 corked bottle 4 drams acacia, 3 drams g-lycerine, 3 drams 

 pure water, thymol ysg-rain. Filter or else strain the 

 completed solution through very fine linen or silk. Hurry 

 it by more heat if desired. Clear the solution of all dirt 

 residue and air-bubbles. Having- this as a mounting- me- 

 dium use white zinc cells and finish as usual. This will do 

 not only for pollen but for starches and other objects. 



RECENT PUBLICATIONS. 



Clinical Diagnosis by Means of Microscope and Chem- 

 ical Methods.— Charles E. Simon, M. D., 2d ed., 133 cuts 

 and 14 lithographic plates. Lea Bros. & Co.. 1897. This 

 is an up-to-date book on blood, urine, feces and other thing-s 

 where the microscope may play its part. 



Essentials of Bacteriology.— By Dr. M. V. Ball, 218 pp. 

 $1.00. The 3d Edition has just been issued by Saunders, 

 Phila., and g-ives the characteristics of 275 bacteria. 



Lea Brothers & Co., of Philadelphia have just published 

 a new, fourth edition of Abbott's Bacteriolog-y of 543 pag-es 

 with 106 illustrations. Chapters are added on the bubonic 

 plag-ue, influenza and g-onococcus. Price $2.75. 



