LAWS OF HEREDITY. 15 



race), may, and perhaps does, furnish a solution of the secret of the prosperity 

 of the Aryan race. In other words, a correct theory may be formulated thus : 

 That the most prosperous nation is that in which there is the least percentage 

 of marriages between near relatives, and also the least between persons of 

 difterent races. Numerous instances, tending to establish the correctness of 

 this theory, both as to man and animals, might be adduced ; and much evi- 

 dence, botli of a positive and negative character, could be presented to sup- 

 port this view. Of the latter kind, may be offered the acknowledged want of 

 physical stamina, as well as frequent infertility, of the Mulatto and Mestizo — 

 the women of the Papuan race, after crossing with the European, are nearly all 

 barren, or, if they have offspring, they are much enfeebled, botli physically 

 and mentally. It is known that the progeny of a cross between the Christian 

 and Jew, or other Semitic race, is almost universally more or less enfeebled. 

 To such an extent had this obtained in the French province of Algeria, that a 

 committee of the Climatological Society of France, sent to Algeria to investi- 

 gate the subject, otficially reported to their Government that, in the acclimati- 

 zation of Europeans in that country, alliances should not be allowed, under 

 any circumstances, with the Arab race, as it was in process of deterioration, 

 and final extinction ; while intermarriage with the Latin races, planted on 

 the shores of the Mediterranean (Spaniards, Italians and Maltese), should 

 be encouraged, as they showed a much higher degree of fertility and vitality. 

 The Jew holds it to be a religious duty not to intermarry with the Aryan 

 race ; and it is perhaps owing to tlieir knowledge of these physiological facts 

 that they discourage such alliances. 



In animals, the mule, or any mongrel breed, is more or less defective in 

 some of the characteristics of the original species. As a rule they are sterile. 



Attempts have recently been made to bring the theory or laws of transmis- 

 sion by descent into disrepute, by assuming that, in accordance with these 

 laMS, a one-legged man should procreate a one-legged offspring. But the 

 learned and indefatigable physiologist, Dr. BroAvn-Sequard, has recently made 

 some singular discoveries upon tliis sul)ject, which go far toward showing that 

 even tliis apparent impossibility may be overcome. Brown-Sequard does not 

 as yet chiim that the one-legged breed is to be looked for at a very early day; 

 but he has demonstrated, by a series of conclusive experiments on Guinea pigs 

 (liis favorite animals for experiment), that injuries to parents do result in the 

 production of offspring with analogous lesions. I will give, briefly, some of 

 his conclusions concerning the hereditary transmission to animals of morbid 

 states, caused, in one or the other of the parents, by injury to the nervous 

 sj-stem. 



1*^. A change in the shape of the ear in animals born of parents in which 

 such a change was the result of a division of the cervical sympathetic nerve. 



2d. A partial closure of the eyelids in animals born of jiarents in which 

 that state of the eyelids had been caused, either by section of the cervical 

 sympathetic, or removal of superior cervical ganglion. 



3d. UxojMhahnia in animals born of parents in which an injury to the 

 rcxf/forin body had produced that protrusion of the ey(;ba]l. 

 ■ 4ith. Ha^matoma and dry gangrene of the ears in animals born of jjarenis in 



