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THE AMEBIC AX NATURALIST [Vol. XLVII 



decidedly indicated by the type of offspring to which they 

 give rise, whether they are mated together or with nor- 

 mal individuals. 



Effects on the Offspring 



The animals have been mated in various combinations. 

 First, treated males have been paired with normal 

 females, the paternal test; this is the crucial test of the 

 influence of the treatment on the germ cells. In this case 

 the chemically modified or weakened spermatozoon can 

 alone be responsible for the defective offspring, since the 

 egg is normal and develops in a normal environment in 

 the healthy mother. 



Second, treated females are paired with normal males, 

 the maternal test. This combination offers two chances 

 for injuring the offspring. Either the ovum may be 

 defective as the result of the treatment which the mother 

 has undergone, and may thus give rise to a defective 

 individual; or secondly, the developing embryo may be 

 affected directly by the alcohol in the system of the 

 mother, since Nicloux has shown that this substance may 

 pass from the blood of the mother into the tissues of the 

 fetus. Thus the intoxication of the embryo may modify 

 its forming structures in the same way that a fish embryo 

 develops deformed organs and parts when in sea-water 

 to which alcohol has been added. 



The third combination is the mating of two alcoholic 

 individuals. This is the most severe test and offers the 

 greatest chance for defective offspring. 



Before the experiment or treatment begins the guinea- 

 pigs are all tested by normal matings and are found to 

 give normal vigorous offspring. They continue to give 

 normal offspring until the treatment has lasted for some 

 time. The effect accumulates slowly and is not noticed 

 at once. A number of experiments in which the treat- 

 ment of a female was commenced at the beginning of 

 pregnancy have so far given rather indefinite results, 

 although a slight effect may be indicated. 



