Heredity. 



consider this latter subject at the outset. This we will do very 

 briefly, referring the reader for fuller details to special treatises. 

 It will suffice to show, by means of a few definite and well-ascer- 

 tained facts, that heredity extends over all the elements and 

 functions of the organism ; to its external and internal structure, 

 its maladies, its special characteristics, and its acquired modifi- 

 cations. 



The first thing that attracts the attention, even of the un- 

 observant, is the heredity of the external structure. This is a fact 

 of everyday experience, and nothing is more common than to 



> hear that such and such a child is the image of its father, mother, 

 or grandparents. Hereditary influence may manifest itself in the 

 limbs, the trunk, the head, even in the nails and the hair, but 



- especially in the countenance, expression, or characteristic features. 

 This is an observation made by the ancients ; hence the Romans 

 had their Nasones, Labeones, Buccones, Capilones, and other names, 

 derived from hereditary peculiarities. According to Haller, the 

 Bentivoglios had on their bodies a slightly prominent tumour, 

 transmitted from father to son, which warned them of changes 

 in the weather, and which grew larger whenever a moist wind 

 was coming. The resemblance may be so close as to give 

 rise to doubts concerning personal identity, or at once to betray 

 parentage. Ten years before his death a singer at the opera, 

 named Nourrit, appeared on the stage with one of his sons, 

 who had inherited his physical constitution as well as his pleasing 

 voice ; and in a play with a plot like that of the Menac/imi, the 

 extraordinary resemblance of the son to the father added a 

 hundred-fold interest to the endless misunderstandings with which 

 the play was filled. 1 These hereditary resemblances have some- 

 times led to the most unexpected and most romantic adventures, 

 so that it is not surprising that Marryat has turned them to 

 account in his novel, l japhei in Search of a Father? 



It is still more singular that this resemblance between parents 

 and children may undergo such metamorphoses as shall cause the 

 child to resemble at one time the father, and at another the 



1 P. Lucas, Traiit Fhysiologique et Phttosophique de VHertdtie Naturelle, 

 vol. i. p. 195- 



