200 MARRIAGE AND DISEASE. 



proportion of those born ever arrive at maturity, and 

 few indeed reach old age. Sooner or later in life 

 the majority of these persons develop consumption ; 

 many are so carried off even in infancy ; great numbers 

 succumb before or about the time of adolescence, and 

 only a small remnant live beyond thirty-five or forty 

 years of age. 



Persons of this phthisical temperament are also 

 remarkably prone to fatal degenerative changes (fatty 

 degeneration) of certain vital organs, as the liver and 

 kidneys. It is also to be noticed that in them the 

 generative organs are often but poorly developed ? 

 which in itself is positive evidence of progressive 

 decay of the stock. It is true that the intellectual 

 faculties are often active and well developed, but even 

 here there are unmistakable signs of the decay which 

 has attacked the system generally. However brilliant 

 intellectually, they are as a class emotional, impres- 

 sionable, and impulsive, and there is a marked absence 

 of that stability which indicates true mental strength. 

 From slight causes they develop convulsions in 

 infancy, chorea, hysteria, and other nervous disorders 

 in youth, and acute attacks of insanity in adult life. 



This diathesis appears to be built up with equal 

 certainty by impure air, drunkenness, and want 

 among the poor, and by dissipation and enervating 

 luxuries among the rich. From either set of causes 

 it is capable of rapid development, and it is trans- 

 mitted to the offspring with very great certainty. 

 By injudicious marriages and persistent ignoring of 



