BIRTH-MARKS AND TELEGONY 403 



in telegony though not a proof of the reality of tele- 

 gony that amongst breeders of horses and dogs the 

 selling value of a dam which has borne young to an 

 inferior sire or to one of a distinct species, is largely 

 diminished as compared with that of a dam which has 

 been mated with a first-rate sire of her own breed. 

 Darwin himself was led, by his inquiries into a similar 

 occurrence in plants, to favour the notion that a sire 

 could so " infect " a mare that her offspring by a later 

 sire would in some instances show traces of the characters 

 of the earlier sire. The parts of a plant which form the 

 coverings of the fertilized ovule, the " coats " of the seed 

 and the seed-case and fruit, are, of course, parts of the 

 maternal plant. In each of the ovules which grow in 

 the central part of a flower (the so-called " pistil ") is an 

 egg cell like that of an animal. This is " fertilized " by 

 the pollen-grains which are brought by wind or by 

 insects from the " stamens " of another flower. Each 

 pollen-grain thus brought to the surface of the pistil 

 elongates into a delicate filament, and penetrates into 

 it, and so reaches an egg cell, with which it fuses. Then 

 the surrounding tissues grow and swell up, forming the 

 seed coats and the fruit. They are parts of the egg- 

 cell-producing or " mother " flower. Thus the pulp and 

 " rind " or skin of an orange is part of the mother plant, 

 not of the germs or young embedded in the " pips." It 

 is found that if an orange-flower is deliberately fertilized 

 by placing on its pistil the pollen-grains of a lemon- 

 flower, not only are the ovules of the orange fertilized, 

 but the surrounding structures, which enlarge to form 

 the fruit and are parts of the orange plant quite distinct 

 from the ovules, also become affected by the pollen. In 

 one well-observed case when an orange-flower was 

 fertilized by a gardener with the pollen of a lemon-flower, 

 the skin or rind of the resulting fruit was found to 



