MOVEMENTS IN THE VISUAL CELLS 



153 



TABLE 1 



Measurements from the retinas of four Atneiurus which had been kept at 5°C. in Iht 

 dark. The values are in micra and represent measuretnents taken along axe-- 

 coinciding loitK radii of the eyeball 



Measurements from the retinas of four Ameiurus which had been kept at 25°C. iit 

 the dark. The values are in micra and represent measurements taken along axex 

 coinciding ivith radii of the eyeball 



is subtracted from the iiieaii values, the relation existing be- 

 tween the corresponchng vahies at either end of the tenii)er- 

 ature range will be expressed by the following proportion: 

 25°C: 5°C. =3:2. The variabiUty in the length of adjacent 

 rods in any section is relatively so great that this disparity in the 

 length of the myoids is not apparent until actual nieasuTements 

 are made. 



In a few observations upon the effect of temperature on the 

 extended rods in the light, the range at 25°C. seemed to run higher 

 than at 5°C. by 15 to 20 per cent. The lengths of the extended 

 inner members were approximately 50 m at 5°C. and 60 p. at 25°r. 

 Similar tendencies will be noted among certain other fishes. 



THE JOURNAL OF COMPARATIVE NEUROLOGY, VOL. 26, NC 



