ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 895 



substance green ; nervous tissue clearly differentiated. Eosin, 

 gentian-violet, methyl-blue, safranin, fucbsin, tropseolin, malachite- 

 green, and Bismarck brown may be used instead of methyl-green. 



If the sections treated with turpentine stains are put in a mixture 

 of pure turpentine oil and absolute alcohol, the colour slowly fades 

 from the plasma. The author used Mayer's carmine solution, the 

 formula for which he communicates as follows: — 100 cc. of absolute 

 alcohol are boiled with four grm. carmine and twenty-five drops of 

 hydrochloric acid added. This solution is placed drop by drop in a 

 mixture of turpentine oil and absolute alcohol, and the turpentine oil 

 to be used is mixed with it. Staining is almost instantaneous. 

 Double staining is possible. Hematoxylin powder dissolved in abso- 

 lute alcohol and introduced in turpentine oil gives a nuclear stain. 

 The bright brown nuclei assume a violet colour in ammonia vapour. 

 The absolute alcohol must be pure and free from acid. The tur- 

 pentine colours are to be kept in glass bottles. 



Isolating the Primitive Muscular Bundles and Staining Nerve- 

 endings.* — Dr. G. Sandmann gives a new procedure for isolating the 

 primitive muscular bundles and for staining nerve-endings. 



For isolation the author employs a solution of sulphuric acid and 

 distilled water. The muscles are put with the acid in a test-tube, 

 either in toto, or if their size require it, are dissociated in pieces 

 parallel to the fibrillation. Here they remain from one to eight 

 days according to their thickness or richness in connective tissue. 

 The muscles are then washed, and boiled several times in distilled 

 water. Before each boiling it is necessary to allow the water to cool 

 or to replace the hot with cold water, since the glue formed from the 

 connective tissue through the heat and acid loses its coagulability and 

 becomes easily soluble in water. Muscles thus treated are easily 

 dissociated throughout their whole length into their primitive fibrillfe. 



In staining, for which purpose Dr. Sandmann uses gold chloride, 

 he departs from the usually accepted view that only fresh muscle- 

 fibre gives good gold preparations, and exposes muscle-fibres treated 

 with sulphuric acid to the influence of the gold chloride. He lays 

 the separated muscle-fibres in a dilute gold solution (one to three 

 drops of a 1 per cent, gold chloride solution to 10 cc. water) until 

 they take on a yellow colour. After having been washed several 

 times in water acidulated with acetic acid, the muscle-fibres are boiled 

 for a few minutes in order to cause the reduction of the gold. The 

 muscle-substance becomes of a red to a deep-blue colour, the nerves 

 are darker, even black. 



As in all gold staining, this method has the defect of inconstancy 

 of stain, but from its easy practicability, it permits, without trouble and 

 waste of time, the preparation of a large number of specimens, among 

 which some few will always be found well stained. The method gave 

 very favourable results in the examination of mammalian muscular 

 fibres, which are only dissociated with difficulty, and also in the study 

 of degenerative changes of nerve-end apparatus. 



* Arch. f. Anat. u. Physiol.— Physiol. Abtli., 1885, p. 240. 



