42 SELECTED NOTES FROM 



from dust in the meanwhile. Rev. W. W. Spicer speaks in the 

 highest term of this process, saying — " I have had the opportunity 

 of examining sHdes of Desmidiaceae prepared in Dresden after Herr 

 Hantsch's method. Nothing can exceed the beauty of these pre- 

 parations ; the form of the plant, and the colouring of the endo- 

 chrome, having undergone no change whatever." — Johann Nave's 

 Handy-book, p. 59. 



T. West. 



Mounting Dry Opaque Objects without Cover -Glass.— Dr. 



Carpenter, in his work on the Microscope, Sec. 155, p. 209, says 

 that he has a large collection of objects mounted in this way, and 

 as regards myself I will add that my rather extensive collection of 

 Polyzoa is for the most part without cover-glasses. I find that — 



I St. — Objects are better seen by reflected light when there is 

 no cover intervening. 



2nd. — You avoid the condensation of moisture on the under side 

 of the cover-glass, which, after a time, damages good slides. 



3rd. — A still worse evil which, unfortunately, very frequently 

 occurs, viz., a beautiful growth of a Fungus ( Penicilmm)^ 

 interesting in itself, but a dangerous intruder into the 

 cabinet. When the object to be preserved is delicate, it 

 should undoubtedly be covered, and the risk of these evils 

 must be incurred. 



[This may be in a great measure prevented by previously wash- 

 ing the object to be mounted in a solution of carbolic acid, and 

 thoroughly drying before mounting. — Ed.] 



But where it is of a coarser character, much is gained and 

 nothing lost by leaving it uncovered. The slides may be laid flat 

 upside-down in the cabinet, and labelled on the back^ or^, as Dr. 

 Carpenter says, a number of them may be packed closely together 

 in boxes or held by an elastic band. Much economy in space is 

 thereby gained, and no dust enters, and if dust is observed, the 

 coarser objects I speak of may be lightly brushed with a soft camel- 

 hair pencil. I may add that the cedar slips I use are cheaper than 

 the more complicated way of mounting ; they cost 6d. or 8d. per 

 dozen, and I make the bottom to the cell by fixing on a piece of 

 black paper. 



G. D. Brown. 



False Crystals in Becolourised leaves.— I should like to ask, 

 Is not the process of decolourising leaves by chlorinated soda likely 



