386 



WILSON GEE. 



causes and as the result of treatment are included in the per- 

 centage sub-normal recorded. Since development in this fish 

 is well advanced at the end of the sixth day circulation is well 

 established by the third or fourth day, and the eyes well formed 

 by the end of the sixth day this is the period at which most of 

 the experiments were terminated. This was done for practical 

 experimental purposes, since to record observations on so large 

 and rapidly accumulating a series would be almost an impossi- 

 bility. 



TABLE II. 



SHOWING COMBINED RESULTS OF THE SEVERAL EXPERIMENTS ON EGGS PRIOR 



TO FERTILIZATION. 



Examination of the accompanying table (see Table II.) will 

 show that the percentage of sub-normals in the controls scarcely 

 averages four per cent. In the dishes that were treated with 

 two per cent, alcohol this varied from sixteen per cent, sub- 

 normal to as high as ninety, with an average of fifty per cent. 

 In almost every lot there were at least a few which came through 

 their development normally. It was also frequently noted that 

 where in earlier development every individual in a dish appeared 

 abnormal, later on with circulation successfully established, the 

 early deformity became regulated, and at the end of the sixth 

 day the individual was included among the normal. 



The effects of the five per cent, alcohol were more deep seated. 

 In some instances only one individual came through to the end 

 of the sixth day, and this was very abnormal. The types of 

 defects produced in these treatments are considered in another 

 part of this paper. 



2. Immediately after Fertilization. 



(a) Condition of Egg at this Period. It has been shown by 

 Loeb ('13) and others that the entrance of the spermatozoon in 



