666 SUMMARY OF CURRENT KI'.SKARCHES RELATING TO 



washed in running water for 24 hours. For washing, a funnel with a 

 siphon stem was used. This, when placed under a tap, kept filling and 

 emptying automatically. A large number of pieces, if properly labelled, 

 can be washed by this method at the same time. 



The pieces were next dehydrated in absolute alcohol, cleared up in 

 xylol, and imbedded in paraffin. Impregnation with paraffin should be 

 done as quickly as possible, as protracted immersion in xylol tends to 

 dissolve out the fat droplets. The sections may be mounted unstained in 

 glycerin or stained for 24 hours in safranin. The safranin was a strong 

 alcoholic solution mixed with ariilin water. Magenta red and picric 

 acid were also used, but the effect was less delicate. 



Staining Nerve Endings in Skin of Mammals.* — A. S. Dogiel 

 used a 1-2 p.c. solution of silver nitrate wherein were placed small pieces 

 of skin, the solution being incubated at from 34°-36° C. for 3-5 days. 

 The pieces were quickly washed in distilled water and then transferred 

 to the reducing solution of formalin and pyrogallic acid for 3-5 days. 

 If the silver had been reduced the preparations were washed in distilled 

 water, then hardened in absolute alcohol, and, after imbedding in celloidin, 

 were sectioned. 



Examination of Cultures and Smears from Throat and Nose.f — 

 W. T. Gr. Pugh recommends the following procedure for detecting the 

 presence of diphtheria bacilli in exudations of the throat and nose. 

 The stain consists of toluidin blue 1 grin, dissolved in 20 c.cm. 

 absolute alcohol and 1 litre of distilled water, to which 50 c.cm. of 

 glacial-acetic acid are added. The films and smears should be stained 

 for two minutes or longer. When examined by artificial light the 

 Babes-Ernst granules, whether in bacilli or cocci, are seen to be stained 

 reddish-purple, the diphtheria bacilli thus standing out prominently. 



Staining Nerve Fibrils.J — According to A. Bethe the staining of 

 nerve fibrils is due to the presence of an acid, " fibril acid," which is 

 insoluble in ether. He gives three methods. (1) The old ether method, 

 which is uncertain as to its results. The piece of fresh tissue is placed 

 in ether, which is frequently changed. After two days it is transferred 

 to a solution of toluidin blue, 1 : 3000, and on the following day to 

 ammonium molybdate. It is then imbedded and sectioned. (2) New 

 ether method. The fresh tissue is first treated with ether, and after- 

 wards dehydrated with absolute ether. It is then transferred to xylol 

 and afterwards imbedded. (3) Ammonia method. Fix with alcohol, 

 to 7-10 parts of which 1 part of ammonia is added ; imbed and stain 

 as before. 



Use of Electrolysis for the Metallic Impregnation and Staining 

 of Tissues.§ — L. Sanzo places the two electrodes of a battery in a basin 

 filled with distilled water. To the negative pole is fixed a piece of tissue 

 previously impregnated with nitrate of silver. A weak current is then 

 passed and this decomposes the silver nitrate, the acid radicle going to 



* Anat. Anzeig., xxvii. (1905) pp. 97-118 (10 figs.). 

 t Lancet, 1905, ii. pp. 80-1. 

 J Zeitschr. wiss. Mikrosk., xxi. (1904) pp. 344-8. 

 § Anat. Anzeig.. xxvii. (1905) pp. 269-70. 



