674 SUMMARY OF CURRENT RESEARCHES RELATING TO 



different nnininls, being most favourable in Roptilia, most uufavotirablc 

 in the osseous fishes and in the luvertebrata. 



Staining Nerve-endings with Gold Chloride.* — Dr. G. Boccardi 

 roconinicuds the following metliud for staining nerve-endings in niusclo 

 witli gold. 



The muscles are treated by Eanvier's method with lemon juice and 

 gold chloride, or the mixture of gold chloride and formic acid ; they aro 

 then washed in distilled water and the preparations laid for about 

 2 hours in a O'l or even 0*25-0 "3 per cent, solution of oxalic acid. 

 A still better mixture is, acid, formic, pur. 5 ccm. ; acid, oxalic. 1 per 

 cent. 1 ccm. ; aq. destil. 25 ccm. Then wash in water, and mount in 

 glycerin. 



Weigert's Haematoxylin Method as applied to other than Nervous 

 Tissues.| — Dr. P. Schicffurdecker states that Weigert's hjematoxyliu 

 ferridcyanide method can be usefully employed on other tissues than 

 nervous, for example it shows the nuclei of connective tissue well, but 

 has little or no effect on lymph-corpuscles, hence its ajiplicability to 

 lymphatic glands for distinguishing between the framework of the gland 

 and the corjniscles. It seems to have different actions on blood- 

 corpuscles, but it is on the epithelium that its speciality is prominent, 

 the sweat-glands, blood-vessels, and nerves standing out very clearly. 

 Yet on the whole the method seems uncertain, and it is questionable 

 how far the chemical, and how far the physical properties of the tissues 

 are the important factors. 



Staining Mitoses.:): — Dr. G. Bizzozero and Dr. G. Vassale found the 

 following method gave the best results for fixing mitoses. 



The sections made from pieces hardened in absolute alcohol were 

 placed for 5-10 minutes in Ehrlich's fluid (gentian violet 1, alcohol 75, 

 anilin oil 3, water 80), then rapidly washed in absolute alcohol, and 

 then transferred to chromic acid solution 1:1000 for 30-40 seconds, 

 whereupon they were rejilaced in absolute alcohol wherein they lost part 

 of their colour. To better fix the mitoses it is well to put the sections 

 back again in the chromic acid solution, and afterwards in absolute 

 alcohol. After 30—40 seconds they are placed in oil of cloves ; this 

 process may be required to be repeated like the last stage. When no 

 dye is any longer given off" in the cloves, the sections may be mounted in 

 dammar. This method gave good results with all tissues and organs. 

 In many cases, however, a still better result was attained by treating 

 the sections, previously to the chromic acid, with the Gram iodine solution 

 (iodine 1, potassium iodide 2, water 300). The former method was 

 found better for lymphatic glands, the latter for those organs in which 

 the nucleus is easily decolorized, e. g. liver, salivary gland, kidney, &c. 

 The foregoing staining method is also available for prejiarations stained 

 in Flemmiug's chrom-osmium acetic acid mixture ; the sections, however, 

 must be well washed before they are placed in absolute alcohol. But 

 whatever the hardening method, the cell-substance was uncoloured or 

 slightly yellowish ; in resting nuclei the nucleoli were slightly stained 

 while the mitoses were violet or almost black. 



* Lavori cscguiti nell' 1st. fisiol. di Napoli, 1886, p. 27. 



t Anal. Anzeig., ii. (1887) pp. GSO-4. 



t Arch. f. Pathol. Anat., ex. (1887) pp. 1G5-244 (1 pi). 



