EFFECTS OF ALCOHOL ON GERM CELLS OF FUNDULUS. 



389 



cleavage stage, only a small percentage were observed to be 

 cleaving in these when the control showed a large proportion. 

 It will be noted though that in all of the dishes except the one 

 treated with twenty-five per cent, alcohol the percentage develop- 

 ing is as good as that of the control. A number of eggs were 

 prevented from developing at all by treatments of this higher 

 strength. 



The types of defects secured by these short length treatments 

 are much the same as those reported by Stockard ('10) from 

 longer treatments of the eggs with lower percentages and be- 

 ginning in the early cleavages. This is particularly true with 

 the ten and fifteen per cent, strengths used. 



3. One Hour after Fertilization. 



The eggs of Fund ill us cleave normally about two hours after 

 fertilization. At one hour after fertilization, preparations must 

 be well along in the cell for the formation of the first cleavage 

 figures. The eggs seem considerably more resistant at this 

 period as reference to the accompanying data will indicate (see 

 Table IV.). This is no doubt due in part to the altered character 



TABLE IV. 



RESULTS OF TREATMENT OF EGGS WITH SEA-WATER SOLUTIONS OF ALCOHOL 

 FOR ONE-HALF AND ONE HOUR AT ONE HOUR AFTER FERTILIZATION. 



Series I. (treated for one-half hour). 



Series II. (treated for one hour). 



1 Most of the individuals of this lot were considerably weakened as compared 

 with the control but not sufficiently to be classed as defective. 



