326 SUMMARY OF CURRENT RESEARCHES RELATING TO 



one or two weeks. He also used one-third alcohol for 24 hours, followed 

 by staining with rosanilin nitrate or dilute Eenaut's hfematoxylin-glycerin, 

 to show the granular circle round the nucleolus of the goblet-cell nuclei 

 in the bladder of various amphibia. The best results were obtained from 

 sections. The objects were either placed for some days in Miiller's fluid 

 and then hardened successively in 50, 70, 90, and 100 per cent, alcohol, 

 or were left in 0-5 per cent, osmic acid for 24 hours and then hardened 

 gradually in spirit. But excellent results wore also given by 2 to 3 days' 

 hardening in 0-25 per cent, chromic acid, followed by washing in water 

 for 24 hours, and this by gradual hardening in spirit, or by a 24 hours' 

 action of Fleraming's chrom-osmium-acetic acid, and after hardening in spirit. 

 The objects were imbedded in celloidin, then cut and stained in the manner 

 previously described,* although it may be mentioned that rosanilin nitrate 

 and Weigert's Bismarck brown are excellent for the purpose. The sections 

 were overstained, and the excess of colouring matter extracted in absolute 

 alcohol, and then after dehydration and clearing up in bergamot oil, were 

 mounted in balsam or dilute glycerin. For the connections between the 

 goblet-cells and nerve-terminations, a 0*5 per cent, gold chloride solution 

 was used after Eanvier's method. 



Preventing Cartilage-cells shrinking away from Matrix. t — Mr. B. L. 

 Oviatt states that Prof. Gage finds that the following mixture is superior 

 to the saturated solution of picric acid, recommended by Ranvier for pre- 

 venting cells shrinking away from the matrix : Picric acid, 7 • 5 grns. ; 

 alcohol (95 per cent.), 250 c.c. ; water, 250 c.c. After 24 hours the 

 Bections are transferred to water, wherein they remain for 6 to 12 hours. 



Demonstrating the Nuclei of Mammary Gland-cells in Lactation.^— 



Dr. F. ISissen used as his material the glands of suckling bitches, rabbits, 

 and cats. The animals having been killed by cutting their throats, the 

 glands were quickly removed and cut into small pieces, some of which were 

 placed in a concentrated sublimate solution heated to 40° C, and others 

 in Flemming's chrom-osmic-acetic acid mixture. After twelve hours the 

 pieces from the sublimate solution were washed in flowing water for 

 twenty-four hours, and then hardened in alcohol. When sufficiently hard 

 they were passed for twenty-four hours into a one per cent, watery solution 

 of logwood, and thereupon for another twenty-four hours into a one per 

 cent, alum solution (changed five or six times). In order to obtain a pure 

 nuclear stain, the colour must be extracted with the alum solution until the 

 extraction fluid is but little tinged. The protoplasm is either unstained 

 or has merely a faint bluish reflex, the chromatin of the nucleus alone is 

 stained ; the connective tissue is unaltered, but the lymph corpuscles are 

 deeply dyed, so that by the degree of stain they are easily discriminated 

 from the nuclei of the alveolar epithelium. The coloured pieces were 

 dehydrated with absolute alcohol saturated with turpentine oil, imbedded 

 in paraffin and cut with a microtome. The pieces kept in Flemming's 

 mixture were after two or three days washed for twenty-four hours, hardened 

 in absolute alcohol, and imbedded unstained in paraflfin. The sections were 

 freed from paraffin by means of turpentine, and the lurpentine removed by 

 alcohol. 



Gram's method was used for staining. The staining fluid is a solution 

 of 3 grms. anilin, 1 grm. gentian violet, in 15 absolute alcohol, with addition 

 of 100 grms. of aq. dest. When removed from alcohol the sections are 



* See this Journal, 1885, p. 002. 



+ St. Louis Merl. and Surg. Journ., li. (1886) p. 209. 



J Arch. f. Mikr. Anat., xxvi. (1886) pp. 337-42 (1 pi.). 



