516 Journal of Applied Microscopy. 



Jenner, L. New Preparation for Rapidly Fix- The author uses a mixture of equal 

 ing and Staining Blood. The Lancet, 688- parts of 1.2 — 1.25 per cent, of Griibler's 

 ' water-soluble eosin in distilled water, 



and a one per cent, solution of Griibler's medicinal methylen blue. These are mixed 

 in an open basin, stirred well with a glass rod, filtered after 24 hours, and the 

 residue dried in the air or an incubator at a temperature not exceeding 55 degrees 

 C. When dry this is powdered, shaken with distilled water, washed on a filter, 

 dried and again powdered. 



For use .5 gram is dissolved in 100 cc. of pure methyl alcohol and the filtrate 

 used as the fixative stain. Cover glass preparations are made by pouring a few 

 drops of the solution on a dry blood film, allowing it to remain for 1 to 3 minutes. 

 The stain is poured off, the cover-glass rinsed in distilled water for 5 to 10 sec- 

 onds, until the film becomes pink. The cover-glass is then dried in the air. 

 Red corpuscles are terra-cotta. colored, the nuclei of white cells blue, platelets 

 mauve, the granules of the polymorphonuclear white cells and myelocytes are 

 red ; those of the basophile or mast cells dark violet, and bacteria filariae and 

 malarial parasites blue. a. m. c. 



The author has repeated Maupas' 



Joukowsky, p. Reproduction of the Ciliata. famous experiments, and the somewhat 

 Zool. Centralbl. o: 42-43, 1899. ^ 



varying results reached by the two ob- 

 servers show us the need for caution in considering this question. 



In Fleurotricha lanceolata over 458 generations were observed without the 

 occurrence of degeneration. The size of the individual depends on nutrition 

 mainly ; the rate of multiplication varies markedly with the temperature ; disturb- 

 ances are apparently produced by the accumulation of waste products in the 

 water, and degeneration seems to be due not merely to the number of the gener- 

 ations, but also the rapidity of "their succession. 



Param(eciuni caudatum showed no nuclear degeneration even after 5 month's 

 culture, but the cilia were markedly reduced and the animals were sluggish in 

 consequence. 



In P. putrifiuni effective conjugation between the descendants of one individ- 

 ual was observed, but the author admits that this probably has its limits. 



A. M. c. 



The author has taken up some observa- 

 Negri, A. Ueber die Persistenz des Kernes in . 1 1 -^ /inrv~ rvoN • 



den roten Blutkorperchen erwachsener Sau- tions made by Petrone (1 89 < -98) m sev- 

 gethiere. Anat. Anzeig. 16: 33-38, 9 figs, eral different articles on the existence of 



a nucleus in the adult mammalian red 

 blood corpuscle. Negri repeated Petrone's experiment using his methods which 

 give exceptionally definite and clear results. The best preparations were obtained 

 by treating the blood with one-tenth per cent, osmic or picric acid and staining 

 in formic acid carmine. The blood used was chiefly that of man and the dog, 

 and in every point Petrone's rather startling observations were corroborated. 

 Both investigators found that in the adult corpuscle there is present a small, 

 sometimes central, sometimes eccentric body showing a differentiation into a cen- 

 trally darker and peripherally lighter area. Negri also found these structures in 

 adult corpuscles of man and dog and laid particular emphasis on tracing the 



