220 CROSSING AND CLOSE-INTERBREEDING. 



On the other hand, two cousins may marry, who are 

 equally disproportionately developed, and as much so 

 as were the pair last assumed; and no evil be observed 

 to result. The reason will be ; the relationship does 

 not, in such instance, carry with it similarity of defect. 

 Although equally disproportionately developed, they 

 are not similarly so. Relationship, even when there 

 are defects, does not always or necessarily imply simi- 

 larity of defect, in form or structure. One of the two 

 cousins, may, — where the bond of his relationship with 

 his cousin, was his maternal grandmother, — have in- 

 herited his structure from, either, his paternal grand- 

 father, or paternal grandmother, or from his maternal 

 grandfather ; or, where his parent, who was of kin to 

 his cousin, was his mother, he may have inherited his 

 structure wholly or in great degree, from his father. 

 If he derived a structure from either of these, or from 

 all conjointly, or from some only; and, if his maternal 

 grandmother had thus no influence in determining his 

 features of growth ; it is manifest, that the circum- 

 stance of his wife being his cousin, could not occasion 

 any evil in his offspring. 



To ascribe the difference, in the quantity of effects 

 from the same degree of interbreeding, to unlikeness, 

 per se, or to likeness,/*??" se, is absurd. Such an expla- 

 nation is little more than a mere restatement of the 

 phenomena; or, rather, a restatement of some only 

 of the phenomena. For, such an hypothesis fails to 

 cover many facts, — facts which are not merely left un- 

 resolved, but which conclusively negative such an 

 idea. 



