N- NORMAL 
a » 
8- NOSEBLEED 
Bone 
es" Fe 
h, 
; | 
) 
N) 
HOW NOSE BLEED IS INHERITED 
Nothing is known about the first generation here charted, but from then on it appears regularly 
in some of the members of each generation. 
except the regular nose bleeding that 
ceased at the age of 18 to 20. 
Considering that this peculiarity first 
manifests itself at puberty, 1t perhaps 
bears a very close relation to the 
developing sex organs. It may be that 
the internal secretions of the gonads are 
being poured into the system and 
stimulating blood formation faster than 
the body can take care of it, and the 
excess blood leaves the body by breaking 
through the mucous membrane of the 
nose. The superabundance of blood 
would help to account for the rapid 
development and increased activity at 
this period. As the internal secretions 
and the body came to be adjusted to 
each other, we may suppose that the 
phenomenon diminished and_ finally 
disappeared (with the one exception). 
Davenport? gives a few cases of dis- 
eases of the blood and with evidence 
that the tendencies are inherited. The 
peculiarity herein described is probably 
very similar or the same as one Daven- 
port gives under the caption ‘Nose 
bleed (Epistaxis).”’ 
This trait differs from hemophilia in 
that it occurs in both sexes, only for a 
few years, and then disappears; and to 
2 Davenport, C. B. 
“Heredity in Relation to Eugenics,” p. 153. 
(Fig. 14.) 
all appearances the blood coagulate 
normally. 
Some people who suffer from catarrh 
have frequent but irregularly occurring 
nose bleed. This is usually due to the 
erosion of the mucous membrane and 
generally is induced by slight injuries, 
and is in no way correlated with sex 
development. 
One frequently encounters people who 
have a hypersensitive nose, so that very 
slight injuries result in bleeding. This 
trait usually is apparent long before 
puberty; if proper precautions are taken 
bleeding does not occur; and _ the 
absence of bleeding is not followed by 
depression. In fact these cases are 
apt to be weakened by bleeding. Such 
bleeding seems to result from high pres- 
sure of blood on very thin and delicate 
membranes. It is altogether possible 
that individual No. 3 on the chart was 
of this type. 
The accompanying chart well shows 
the distribution of the trait in question. 
The blank spaces in the first and second 
generations are those from whom no 
data have so far been obtained regarding 
the trait. The blank spaces in the 
third generation represent individuals 
New York, 1911. 
133 
