.»:'.(! SUMMARY <>K (TKRENT RESEARCHES RELATING TO 



from carbol-fuchsin arc poor. The best results were obtained with 

 Griemsa's modification of the Romanowsky stain,* which imparted to 

 the spirochetal a distinctly reddish-violet tinge, while the bacteria came 

 out blue. The films which were made from syphilitic sores and dis- 

 charges were dried in the air, fixed for 10 minutes in absolute alcohol, 

 and stained for some hours. The movements of the spirochete may be 

 readily observed in hanging drops. 



Affinity of Artificial Colouring Matters for Connective Tissue.f — 

 Curtis and P. Lemoult record experiments which show that in order to 

 develop the selectivity of connective tissue for certain pigments, it is 

 necessary to work in presence of picric acid or some other tri-nitrite 

 derivative, and moreover to use stains having at least three sulpho group- 

 ings (S0 3 H) fixed in the chromogen and distributed as uniformly as 

 possible. Satisfactory results are obtained from the use of acid fuschin, 

 red-violet, 4 RS and 5 RS, which stain connective tissue red, or from 

 Ponceau S extra, from diamine blue 2 B, or from naphthol black B, which 

 stain respectively red or blue and possess the advantage of being fast. 



Theory of Histological Staining.:}: — G. Halphen and A. Riche, when 

 studying the theory of histological staining, tested the action of dyes on 

 sections of different animal tissues fixed by means of alcohol. The stain 

 was dissolved in a thousand times its weight of water and used cold. 

 After removing excess of stain with water the sections were dehydrated 

 in a mixture of 1 volume absolute alcohol and 3 or 4 volumes of 

 petroleum-ether. It was found that when slight quantities of acid were 

 added to acid dyes their staining property was increased, and a similar 

 effect resulted when basic dyes were treated with alkali. These results 

 are referred to the basic and acid properties of the albuminoids. These 

 properties are profoundly altered by the action of fixatives, such as 

 formalin and Midler's fluid ; so in order to prevent these influences the 

 tissues to be experimented with w r ere dried under bell-jars in the presence 

 of glycerin or of sulphuric acid. Prepared in this way, the sections 

 failed to show the presence of nuclei or cells of any sort, and the tissues 

 were found to possess the property of energetically decomposing oxy- 

 genated water, a property which tissues preserved in alcohol do not 

 possess. 



Multiplex Slide-holding Device for Staining Sections.§ — E. F. 

 Miller describes an apparatus which consists of a series of perforated 

 vulcanised rubber plates, placed in a holder, having a carrying capacity 

 of 26 slides, so that they maybe clamped against a metal plate by means 

 of a thumb-screw. The principal advantages claimed for the apparatus 

 are the saving of time and expenditure of reagents. 



(5) Mounting-, including: Slides, Preservative Fluids, &c. 



Imbedding Microscopic Alg«.||— W. J. V. Osterhout remarks that 

 the most serious difficulty in imbedding microscopic alge lies in the fact 



* J.R.M.S., 1905, p. 115. 



t Comptes Rendus, cxl. (1905) pp. 1606-8. J Tom. cit., pp. 1408-10. 



§ Johns Hopkins Hosp. Bull., xvi. Q905) pp. 132-3(1 fig.). 



|| Univ. California Pub. Bot., ii. (1904) pp. 85-6. 



