ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



847 



Dr. r. Mayer advises that strijis of gelatin plate, such as arc used by 

 lithographers, should be stuck on the cylinder with some very soft 

 paraffin. 



Reichert's small Rivet's Microtome. — The only peculiarity, so far as 

 we are aware, of Herr C. Eeichert's latest form of this Microtome (fig. 231) 



Ficx. 231. 



consists in the arrangement for raising the object-holder, which is effected 

 by a cord which winds round the axis of the toothed wheel a. 



Letulle. — Microtome de precision. 



Bull. Sjc. An nt. Paris, XI. (1886) p. ,S55. 



(4) Staining and Injecting. 



Carmine solution made with Carbonate of Soda.* — Dr. G. Cuccati's 

 improved carmine stain, especially suited for animal tissues, is made as 

 follows : — Warm water 100 cc. ; carbonate of soda crystals 20 grms. ; mix 

 and heat ; add best powdered carmine 5 grms. ; stir and cover. When it 

 boils cease heating, and add absolute alcohol 30 cc. Allow to cool in a 

 partially closed vessel. Next day filter, and add to the filtrate 300 cc. H2O, 

 acidulated with 8 cc. of a 20 per cent, solution of acetic acid. Next add 

 chloral hydrate 2 grms. Decolorize with 100 cc. spirit and hydrochloric 

 acid 1 cc. This carmine acts intensely on the chromatin of the nucleus, 

 showing up the karyokinetic figures quite brilliantly. It stains in toto very 

 well tissues treated with spirit, perchloride of mercury, or Kleinenberg's 

 fluid, in five to twelve hours, according to the size of the piece. Staining 

 of sections or pieces in toto must always be performed in closed vessels, and 

 before decoloration these must be washed for a few seconds in distilled 

 water. This carmine also has the power of removing the pigment from the 

 eyes of arthropods which have been treated with spirit, while it stains the 

 nuclei of the retinal cells at the same time. 



Zeitschr. f. Wiss. Mikr., iv. (1887) pp. 50-1. 



o K 



