(:iiapti:k i 



ACTl()^ Ol COLD wniioLT 

 ICK KOHMAIION 



( )lisci-\;iti(>iis ,-ni(l theories on llie aclioii ol' low leiiiper- 

 ature without ice i'oriii;ilit)ii can he classitied into two 

 g-roups: ]. Those concerned with orgaiiisiiis which die or 

 are injured in the proximity of tlieir freezing point; 2. 

 Those which refer to tiie action of extreme cokl, at tem- 

 peratures at which the material solidities without form- 

 ing ice crystals, that is, vitrities. The study of the first 

 group will he sulxlivided into two sections: one, con- 

 cerning the effects of chilling ahove the fi-eezing i)oint; 

 the other, the action of cold in the snhcooled state. 



1. A<TI()X or cold) IX TIIIO NEIGHBORHOOD OF 

 Till-: FIMvEZING POINT OF PKOTOPLASM 



A. ACTION OF COLD ABOVE THE FREEZING POINT 



This subject has been competently reviewed by Bel- 

 ehradek (1935) in the chapter ''Chilling, Chilling-Coma 

 and Death by Chilling" of his monograi)li ''Temperature 

 and Living Matter". The reader will find in that chap- 

 ter, presented in a condensed tabular form, the data of 

 numerous investigators on the temperatures of cessa- 

 tion of protoplasmic streaming, ciliary movement, cellu- 

 lar multi])lication, gi'owth, metabolic activity and irri- 

 tability. There follows a compendium and discussion of 

 the observations and theories concerning injury and death 

 by cold at temperatures above the freezing point. Nu- 

 merous bibliograi^hical references are given. Since the 

 subject has been already reviewed, we shall jjresent here 

 only a brief outline of the essential points of interest. 

 A few ([uestions which have not been discussed by 

 Belehradek will be considered in detail. For these only 

 will the l)ibliographical references be given. 



Practically all the authors cited by this reviewer have 

 found that chilling l)ecomes injni'ions or lethal only 



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