D. F. Weeks.Biology and Eugenics.7? 
Normal x Normal. 
Under this type of mating we have grouped all those fraternities in which 
both parents are recorded as normal. 
In the study of 76 fraternities there were 441 conceptions; 62 are too 
young for classification or entirely unknown, 103 died before the age of 14 
years. Of the 276 others, 172 are normal, 75 or 27% are epileptic and 
three or 1% feeble-minded, with one insane and 25 tainted, that is, 197 
(172 + 25), or 71% are duplex or simplex in character. (See pages 91, 
92, Table VII.) (Fig. 19.) 
Fig 19.—Here we have two seemingly normal parents with defective 
offspring. The father’s relatives, as far as known, are normal, with the 
exception of a feeble-minded nephew. The mother has an insane uncle, 
an epileptic brother, and a feeble-minded nephew. Of their six children, 
two are normal, one who now appears normal had chorea, one had spinal 
meningitis, is now slightly deaf and inclined to be nervous, one died at 
the age of eight, the third child was an epileptic. The father of this 
fraternity is the. political leader of the town in which he lives, and is one 
of its most prosperous citizens. E, epileptic; F, feeble-minded; A, 
alcoholic; I, insane; d, died; b, born; inf, infancy. 
The results show that these normal parents are not duplex, but simplex, 
and a study of their ancestors justifies this conclusion, for in at least 45 
of the matings, one or both parents descended from tainted ancestors. 
(See page 99, Table C). 
For a graphic illustration of the fitting of the findings to the expectations 
in the six types of matings see curves in 'Fable XI. (page 96). 
Migraine and Alcohol. 
The large number of alcoholic and migrainous parents justifies a special 
study of these matings. 
In 50 matings where at least one parent is migrainous, there were 350 
conceptions, of which number enough is known of 212 to classify 55 or 26%