82 THE AMERICAN MONTHLY [Mch 



there is none more inviting to a 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 piston 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. — Knoioledge, 



