82 THE AMERICAN MONTHLY [Mcli 



there is iioue more inviting to u student, or better adapt- 

 ed to bring into activity all the resources of his judg- 

 ment, than the systematic study of the species of some 

 limited group, provided this is properly combined with a 

 study of the morphology, development, and ecologic re- 

 lations of such a related series. The Fungi and Myceto- 

 zoa offer themselves, in a special degree, as a field for 

 thorough and original systematic study, and students of 

 these groups will therefore be glad to hear that Professor 

 Lucian Underwood, of Columbia University, has just is- 

 sued, in book form, an admirable exposition bearing on 

 the moulds, mildews and mushrooms. 



Air-bubbles. — A simple and effective method for re- 

 moving air bubbles from microscopic mounts is suggest- 

 ted by P. S. Proctor. A small syringe, having a glass 

 barrel, vulcanite mounts, and leather packing to the pis- 

 ton, is the only apparatus required. Select one that is as 

 nearly as possible air tight, unscrew the top and remove 

 the piston. Close the nozzle with a small piece of bees- 

 wax, half fill the barrel with distilled water, and into this 

 drop the section or tissues to be treated. • Replace the 

 piston and screw on the top. The syringe being invert- 

 ed and the plug of wax removed, the air is driven out of 

 the barrel by raising the ])iston till the water begins to 

 flow out of the nozzle, after which close the aperture with 

 the finger and lower the piston. A partial vacuum is thus 

 formed, and the air rapidly escapes from the cells of the 

 tissue, collecting in the point of the syringe. By remov- 

 ing the finger and raising the piston the liberated air is 

 forced out ; this may be repeated several times as long as 

 air is being expelled from the material. The same mode 

 of operating is applicable to objects that are to be mount- 

 ed in Canada balsam if oil of turpentine be used instead 

 of water, and if the objects to be mounted are quite dry 

 before immersion in the turpentine. — Knowledge. 



