572 GENETICS IN RELATION TO AGRICULTURE 



respect to the stature of successive children in the same families. He 

 finds no evidence whatever of saturation, or as he states it of a "steady 

 telegenic influence." 



Maternal Impression. The belief in maternal impression, or in the 

 effect of the pregnant mother upon her growing fetus, is one of the en- 

 during tenets of popular faith. We need not trouble ourselves here with 

 the long series of influences which are supposed to pass from the mother 

 to the unborn child in human beings. Suffice it to state that they are no 

 more varied nor yet more tenable than those cases which have been 

 described for domestic animals. 



Many curious cases from that of Jacob's peeled wands 1 down to those 

 of far more recent times might be cited from the chronicles of maternal 

 impression; but like the belief in telegony, they all spring from the un- 

 scientific attitude of the popular mind toward isolated instances. We 

 suspect for instance that the famous Biblical herdsman used other 

 methods than that of the peeled wands in order to achieve his remarkable 

 results. 



An instance may be given as typical of those which are recounted in 

 support of the belief in the effect of maternal impressions, although in reality 

 it is stronger than most cases. A section of a well-known Scottish herd 

 of Aberdeen-Angus cattle which was separated from an Ayrshire herd 

 by only a wire fence persistently produced, for several successive genera- 

 tions, red and black-and-white calves. But this was the formative period 

 of the breed, and we have already had occasion to mention the diversity of 

 color which characterized Aberdeen-Angus foundation stock. The oc- 

 currence of red and black-and-white calves, therefore, is a simple con- 

 sequence of the cropping out of recessive factors, the Mendelian ex- 

 planation is adequate and satisfactory. Moreover it is not entirely 

 improper for us to call attention to the utter confusion which would pre- 

 vail in herds of Aberdeen-Angus cattle, if this phenomenon were of gen- 

 eral occurrence. We venture to state that very few breeders of solid- 

 colored cattle have had such trouble from the proximity of herds of 

 Holstein-Friesian, Shorthorn, Ayrshire, and other breeds of cattle, not 

 to mention other sources of contamination which might occur. 



But some of the legends of Aberdeen-Angus history are even more 

 curious than this one. It is recorded of the famous breeder McCombie of 

 Tillyfour that he erected a high black fence around his breeding paddock. 

 But it may be expected that McCombie having as his ideal the black 

 polled Aberdeen-Angus cattle used other means of securing a strain 

 breeding pure for the typical Aberdeen-Angus characters. 



Like the belief in telegony, the belief in maternal impressions arises 

 from an unscientific attitude of mind toward evidence in general. The 



1 Cf. Genesis 30 : 3143. 



