ASCOMYCETES EUASCI YEAST 



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Fig. 78. Yeast. Saccharomyces cerevisiae. 1. Single cell with vacuoles. 2. Cells 

 budding x 1500. 3. Numerous daughter cells x 1000. 4. Cell with ascospores x 1200. 

 5. S. ellipsoideus. 1-4 Modified from L,uerssen and Rees; 5 after Hansen. 



Alcohol in its action is a germicide and when applied to the raw surface 

 or wounds it is a stimulant and local anaesthetic, while in concentrated form 

 it is an irritant and even caustic. When placed upon surfaces of the broken 

 skin it causes cooling and contraction of the superficial blood vessels. When 

 absorbed it hardens the tissues. Internally it causes a secretion of saliva and 

 the heart is stimulated by the irritative action of alcohol.. In large amounts it 

 destroys the peptic ferment. Dr. Winslow says : 



Alcohol is essentially a heart stimulant and the most valuable one we possess. It makes 

 the heart beat more forcibly and rapidly, and also increases blood pressure, despite the fact 

 that, normally, alcohol causes dilation of the arterioles. In weakened bodily conditions, 

 with vascular relaxation, alcohol may increase vascular tonicity. The heart and blood 

 vessels are paralyzed by poisonous doses of alcohol and blood tension falls tremendously. 



The local effect of alcohol upon the peripheral nerves resembles) the action after ab- 

 sorption upon the system generally. The nervous system is affected in nearly the same 

 order and manner as by anaesthetics, and the same stages may be observed. The stages 

 include the stimulant, depressant and paralytic. The law of dissolution is demonstrated 

 by alcohol, as the more highly organized centres and those more recently developed in the 

 process of evolution are first to succumb, and in following out this order, the medulla, 

 the first of the higher centres to be developed, is the last to be influenced by the drug. In 

 accordance with this law the cerebrum is first acted upon. The period of excitement is brief 

 and is due in a considerable degree to the increased cerebral circulation and flushing of 

 the brain. It is essential to emphasize the fact that by far the most apparent and decided 

 action of alcohol is one of depression upon the nervous system as a whole. The stimulating 

 influence of alcohol upon the spinal centres is more marked in the lower animals than in 

 man because the brain is proportionately small and poorly developed in the former. The 

 primary stimulating effect of alcohol is shown in man by increased mental activity and ap- 

 parent brilliancy, but acute reasoning and judgment are not enhanced, and in many cases 

 there is almost immediate mental confusion and drowsiness induced. 



