EXPLANATIONS OF TELEGONY 79 



nature of the dam, and not only the reproductive 

 organs, which, according to Romanes and others, are 

 alone influenced. There is no doubt that matter can 

 and does pass from the blood of the embryo into that 

 of the mother in certain classes of mammalia, at any 

 rate. The published Report of the Fourth Inter- 

 national Congress of Zoology, which met in 1898 at 

 Cambridge, contains a paper by Professor Hubrecht, 

 of Utrecht, in which he describes certain blood-cor- 

 puscles formed in the embryo which undoubtedly 

 make their way into the maternal bloodvessels and 

 take part in her circulation. That matter can pass 

 from the bloodvessels of the embryo to those of the 

 mother is further demonstrated by the experiments of 

 M. Charrin, who showed that diphtheritic toxins in- 

 jected into the embryos of a rabbit caused the death of 

 the mother within five days, and further that a rabbit 

 can be rendered immune by injecting anti-diphtheritic 

 toxins into the embryos. 



There is nothing in these experiments to show that 

 the nature of the dam is radically altered ; and in the 

 Equidae, in which, as we have seen, the classical case of 

 telegony occurred, there is a strong presumption 

 against any such transference of blood - corpuscles 

 from the embryo to the mother. Still, taking all the 

 facts into consideration, it appears that, if telegony 

 exists, it is more likely to be brought about by satura- 

 tion than by the direct infection of the ovary ; though, 

 if the former method be accepted, telegony must be 

 confined to the mammals and the comparatively few 

 other animals whose young spend some time in the 

 body of the mother and are not hatched out from eggs 

 which have lost their connexion with the body of the 

 mother at an early stage. 



Before passing on to consider the views of those 

 who hold that telegony does not exist and to see 

 what light the Penycuik experiments throw on the 



