The Influence of External Factors on Development 195 



capable of producing. It appears in this instance rather illogical 

 to state that the extra pressure induced by the addition of sugar to 

 the solutions of NH4CI caused this salt's action to become more 

 pronounced upon the eggs, for as mentioned before the pressure of 

 these mixtures is often below the usual pressure in which the eggs 

 live, and from the experiment cited below we shall find that the 



Fig. 13 An embryo when twenty hours old in LiCI 0.256 m + sugar 0.293 m, the majority of eggs 

 in this solution are in a similar condition, sc, segmentation cavity. 

 Fig. 14 The least affected egg in the above solution. 



Fig. 15 The majority of the eggs in simple LiCl 0.256 m solution show this condition. 

 Fig. 16 The most abnormal egg in the LiCl 0.256 m solution at this time. 

 Fig. 17 A control egg when twent}' hours old. All X 17^ diameters. 



addition of sugar to sea-water solutions of NH^Cl, which are of 

 course hypertonic, furnish rather indifferent results. One might 

 argue on the other hand that salts of the sea counteract the effects 

 of the NH^ ion, but even if this does occur the high pressure does 

 not particularly injure the eggs, and we are still in the dark con- 

 cerning the question why the distilled water solutions of NH4CI 



