560 E. I. WERBER 



genesis has been repeatedly pointed out, and notably by Mall 

 (I.e.)- Neither is it probable that such an increase in the tem- 

 perature of a mammalian female as would yet allow it to survive 

 could materially affect an ovum in utero. 



If, after what has been said, we dismiss the possibility of 

 physical factors as the underlying causes of atypical develop- 

 ment, there would remain only the group of chemical factors. 

 Of the latter the number of those which can reasonably be 

 imagined to be present in the mammalian's body under certain 

 conditions, is rather hmited. They might be some extraneous 

 poisonous substances which may chance to gain entrance into 

 the human (or other mammalian) body, they could also be bac- 

 terial toxines, or, finally, they may be autogenous poisons of the 

 body, such as some toxic products of a disturbed metabolism. 



Of the extraneous poisons which may find a way into the body 

 without killing the individual, but only exerting an injurious in- 

 fluence on it, or on a developing o\iim contained in the latter's 

 uterus, there are probably not many. Alcohol and some other 

 drugs, to which individuals may habitually be addicted, would 

 probably occupy an important place among these substances. 

 Lead-poisoning and phosphoi-us-poisoning might perhaps also 

 be considered under this heading. However, while in the hght 

 of recent data, there is hardly any doubt left regarding the 

 deleterious effect of parental alcoholism on the offspring (cf. 

 Stockard '12) no cases of human monsters are yet known of an 

 alcoholic parentage. The same would apply also to the occu- 

 pational diseases of lead-poisoning and phosphor-poisoning. It 

 cannot be denied that these poisons probably are capable of alter- 

 ing the typical course of embryonic development, but, evidently, 

 they seem to be acting in a degree not sufficient to cause the 

 development to become monstrous. Or, possibly the strength of 

 action of these poisons necessary to produce monsters might kill 

 the parent or bring about its steriUty, and thus, no occasion may 

 exist for human ova to be under the influence of such strong action 

 of these poisons as would very materially alter the coiu-se of their 

 development. The conspicuous lack of data regarding the rela- 

 tion between alcoholism and 'industrial diseases' on the one 



