1891.] MICR(3SCOPICAL JOURNAL. 61 



scopical cement, and use a turn-table, when he will be surprised at the 

 result obtained. — U^. H. S. 



Mechanical Finger. — These are handsome specimens, and if a few 

 of the perfect forms had been selected by this means and neatly arranged 

 it would greatly have enhanced the value of the moinit. — * * * 



Surface Gatherings. — This slide is rather a startling one for users 

 ,)f * * * j.jj^g i(.g^ which has a great reputation for purity. 



^A^ax Cell. — This slide (diatoms in wax cell fastened with rubber 

 cement) came to me with cover-glass otl'and loose in the case. I have 

 put on a new cover. 



OFFICERS. 



Presidents . . . Samuel Lockwood, Ph. D., Freehold, N. ]. 



Mana ers \ ^' ^^' ^^^^^' ^^- ^- {J^esident) Troy. N. Y. 



^ ^'> ' ' j C. M. VoRCE, Cleveland, O. 

 Treasurer, . . . Joseph McKay, 245 Eighth Street. Troy, N. Y. 

 Curator of Cadinet, Chas. E. Hanaman, Troy, N. Y. 



Microscopy for Amateurs. 



By t. charters white, 



QUEKBTT CLUB. 



\_Conitnned from pnge 4-2.^ 



Diatom Mounting. — No branch of microscopical study possesses 

 greater charms than the study of the diatomaceae. The insatiable ap- 

 petite of the diatomist grows by what it feeds upon, and luckily there 

 is no stint, for this class of miscroscopical life is universal in its distribu- 

 tion. It may be met with recent as well as fossil, in fresh water as 

 well as in the sea ; there is scarcely a spot in nature where it cannot be 

 found. 



Diatoms may be obtained all the year round, but are most plentiful 

 in the spring and summer. Each kind has its favorite habitat; some 

 on the algae in the sea and on its shore ; others have to be searched for 

 in the muddy crevices of the rock. One variety, the me/osira, is com- 

 mon in marshes, where they may be recognized as brownish masses. 

 Others may be sought for on the surface of mud. Oyster beds are very 

 productive of diatoms, and the stomachs of these succulent bivalves 

 abound in many varieties. Diatoms are so ubiquitous that he who is 

 bent upon making a collection need never be at a loss for material. In 

 examining ponds, especially in marshes, where the water is brackish, a 

 most abundant gathering may be made, as many as forty-three varieties 

 having been identified in one depth. They are generally found floating 

 on the water as yellowish brown masses, or lying on the surface of the 

 nuid. In sunshiny weather they may be found floating, because, like 

 other vegetables, they give oft' oxygen in sunlight, which floats them to 

 the surface ; and, should a breeze blow over the surface of the pond, 

 this raft of diatoms may be driven to leeward, where they may be gath- 

 ered tolerably free from mud and other impurities. The instrument 

 used to collect them may be anything of a spoon shape, such an one aS 

 resembles a housemaid's dust-pan in miniature, bi^oad and shallow in 

 front and deep behind. This, attached to a long handle, may be 



