380 SUMMARY OF CURRENT RESEARCHES RELATING TO 



For histological purposes, pieces with the heart attached were dis- 

 sected out, and fixed in osmic acid or in Flemming's fluid. Smaller 

 animals were decalcified after fixation by immersion in 70 p.c. alcohol 

 with 2-3 p.c. sulphuric acid. As stains, borax-carmin, ha^malum, 

 and various other varieties of hematoxylin, were used, and also contrast 

 plasma stains ; for histological purposes, iron-hsematoxylin and van 

 Gieson's method. 



Demonstrating Trypanosomata.* — H. G. PHmmer has used the 

 following method for some years and has found it to give uniformly good 

 and accurate results. The specimen is never allowed to dry, there is no 

 skrinkage of cells, and the finest cytological details can be observed. 

 (1) Expose a coverslip to the vapour of osmic acid (1 p.c.) 1 c.cm., glacial 

 acetic acid 8-5 drops, for 2 minutes. (2) Place a drop of fresh blood 

 on one corner of the slip and expose again to the vapour for 30 seconds. 

 (3) Spread the film carefully and expose again for 15-30 seconds to the 

 vapour until the surface appears no longer moist. (4) Place slip in abso- 

 lute alcohol for 10 minutes. (5) Immerse slip in faintly rose-coloured 

 solution of permanganate for 1 minute (2-3 drops of 1 p.c. sol. to 50 c.cm. 

 H2O). (6) Wash in water for 5 minutes. (7) Stain in following 

 modified Romanowsky, made by mixing just before use — azur i. (1 p.c.) 

 1 c.cm. ; eosin B.A. (1-1000), 2 c.cm., H.^O 8 c.cm., for 15-30 minutes. 

 (8) Wash. (9) Differentiate in orange-tannin 30 seconds. (10) Wash 

 well and drain. (11) Absolute alcohol for a few seconds. (12) Alcohol- 

 xylol (2-3) two or three changes. (13) Xylol ; and mount. 



Instead of 7-13 any other method of staining can be used, according 

 to what stnictures it is desired particularly to show. 



Studying Neurosporidium cephalodisci.f — W. G. Ridewood and 

 H. B. Fantham describe a new sporozoon, Neurosporidium cephalodisci, 

 which infests the nervous system of Cephalodiscus nigrescens. The 

 specimens of G. nigrescens obtained by the " Discovery " were fixed, 

 some in 5 p.c. formalin, some in Perenyi's fluid, and some in picric acid 

 solution. Serial sections of the polypides were cut for the purpose of 

 investigating the anatomical structure of this new species of Cephalodiscus, 

 and these sections and some others were utilised for the study of the 

 sporozoon. The majority of the sections (5-7 • 5 yu,) were stained with 

 Ehrhch's hgematoxylin and eosin, others with hgematoxyhn and orange G, 

 or Mayer's h^emalum, or borax-carmin. 



Demonstrating the Fibrillary Structure of Nerve-endings in 

 Cutaneous Tissue. J — Eugen Botezat finds that the methylen-blue and 

 the Golgi methods supplement one another in the study of nerve-endings. 

 For the latter method he adopts the following procedure : — Pieces of quite 

 fresh tissue, from 2-3 c.mm. in size, are immersed in about J litre of 

 1 • 5 p.c. silver nitrate, and incubated at about 37 * 5° C. for three days. 

 On removal they are quickly washed in distilled water, and then placed 

 in the reducing fluid. This consists of 1 grm. pyrogallic acid, 2 • 5 c.cm. 

 formalin, and 50 c.cm. distilled water. In this they remain for about one 



* Proc. Rov. Soc, Series B, Ixxix. (1907) pp. 95-102 (1 pi.), 

 t Quart. Journ. Micr. Sci., li. (1907) pp. 83-4 (2 pis.). 

 X Anat. Anzeig., xxx. (1907) pp. 34-44 (9 figs.). 



