Scientific Proceedings (114). 



reactions are successively modified so that the peristome of 

 Spathidium is brought gradually nearer and nearer until it grasps 

 the Colpidium. In brief, Spathidium in the majority of cases 

 recovers its lost prey, even though the latter may have become 

 removed a distance equal to several times the length of the 

 Spathidium. 



The factors involved here may be products derived from the 

 dead Colpidium, but more probably are directly related to the 

 poisonous secretion liberated by Spathidium itself. In any event, 

 the complex series of reactions exhibited by Spathidium afford, 

 it is believed, a remarkable example of sensing at a distance by 

 a unicellular organism. 



The complete paper will appear in the Journal of Experi- 

 mental Zoology. 



91 (1673) 



The role of the nervous system in the regulation against cold. 1 



By H. G. BARBOUR and E. TOLSTOI. 



[From the Department of Pharmacology, Yale University School of 



Medicine.] 



One of us has shown that a dog placed in an ice-water bath up 

 to the neck exhibits as one of the reactions to cold a concentration 

 of the blood, losing approximately 10 per cent, of its blood fluid. 

 Such extreme temperatures, however, even well-nourished dogs 

 are unable to resist, the rectal temperature falling rapidly. 



Investigating further the mechanism of regulation against cold 

 we attempted to find first a bath temperature which, while not 

 sufficiently cold to lower the body temperature, would arouse 

 distinctly the regulation against cooling. Secondly, on dogs 

 deprived of their nervous regulatory mechanism by section of the 

 cord between the sixth and seventh cervical segment, it was 

 attempted to determine whether the failure to resist the tempera- 

 ture of baths not too cold to be normally withstood is associated 

 with inability to concentrate the blood. 



It has been found that normal dogs will exhibit a fairly efficient 



1 From investigations aided by the Elizal^eth Thompson Science Fund. 



