ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 731 



Application of Borax-methylen-blue in the Examination of the 

 Central Nervous System.*— Dr. H. Sahli recommends the following 

 formula : Distilled water 40, saturated watery solution of raethylen- 

 blue 24, borax solution (5 per cent.) 16. Mix, leave for 24 hours, and 

 then filter. Sections are stained in this solution for 10 minutes to several 

 hours, and then washed in water or alcohol, until the grey substance 

 is clearly distinguished from the deeply blue-stained white substance, 

 dehydrated, clarified in cedar oil, and mounted in balsam, either pure 

 or mixed with cedar oil. The ganglion cells appear pale greenish, 

 and arc clearly differentiated from the blue-stained nuclei of the 

 neuroglia. The most delicate nerve-fibres are stained. 



The author obtains better results with this solution than with the 

 ordinary alkaline methylen-bluo in the examination of the central 

 nervous system for the presence of micro-organisms. 



Preserving Sections of the Nervous System Treated v^rith 

 Bichromate of Potash and Nitrate of Silver.t— To obviate the 

 difficulty of preserving preparations, Signer C. Golgi places a drop of 

 dammar varnish on the section, and allows it to dry in an even layer. 

 He uses slides which have a square hole in the centre, which is closed 

 below with a cover-glass. The section covered with dammar is 

 placed on this, and when the varnish is dry the specimen can be 

 examined on both sides. 



Study of Fat Absorption in the Small Intestine.l — Herr Th. 

 Zawarykin makes use of the following method : — A piece of intestine 

 is treated with hyperosmic acid, washed in water, and placed in 

 spirit for 24 hours. A small portion is then cut between two pieces 

 of elder-pith, in which it is placed in such a way that the villi are 

 turned towards one half and the serous coat towards the other half of 

 the pith. The razor should be wetted v^ith alcohol. The sections 

 can be stained with picro-carmine. 



Preparing the Cloacal Epithelium of Scyllium Canicula.§ — 

 To isolate the goblet-cells, Herr J. H. List uses Miillcr's fluid and 

 alcohol. The preparations are then imbedded in celloidin, cut, and 

 stained with eosin and mcthylen-green. The epithelial cells are in 

 this way stained rose-red, the goblet-cells green. 



Preparing Embryos of Amarsecium proliferum.||— MM. C. 



Maurice and A. Schulgin employ the following methods: — The 

 whole, or Ijcttcr pieces, of the Ascidian arc laid in water with an equal 

 quantity of picro-sulphuric acid. After half-an-hour tliey are placed 

 in alcohol, the strength of which is gradually increased. They can 

 be stained whole with alum-carmine, or treated as follows: — The 

 isolated ova or embryos arc stained with borax-carmino for 15-18 

 hours, treated with hydrochloric acid, washed in 70 per cent, alcohol, 

 and transferred to a very weak solution of Lyons blue for 15-20 



• Zcithclir. f. WiwH. Mikr., ii. (188:.) pp. 49-51. 



t Arch, per Ic Scicnzf; Mcdi.'he, viii. (1884) p. .').'?. 



X Ardi. f. <i. Gesarnint. I'hy.siol. (IMliigcr) xxxv. (1884) pp. 145-57. 



§ KIJ. K. Akfi.l. WiHH. Wion, xc. (1884). 



II Ann. Hci. Nat.-Zooi., xvii. (1884). 



