214 M. F. GUYER AND E. A. SMITH 
somatic element, its germinal correlative would doubtless remain 
relatively constant, but with any pronounced change in the 
soma such as might give rise to the formation of antibodies or 
kindred substances in the blood serum—for example, degenera- 
tive changes in such an organ as the eye—a corresponding change 
might be induced in the germ. This hypothesis would seem to 
be of special value in accounting for progressive degenerative 
changes in successive generations as in the formation of vestigeal 
organs. 
That this conception of changes in the blood serum being occa- 
sioned by changed conditions in the tissues is not fanciful is evi- 
dent when we recall that exactly such a condition arises during 
pregnancy. The Abderhalden (’13) serodiagnosis of pregnancy 
is based on the fact that a proteolytic ferment capable of split- 
ting placental material into simpler substances appears in the 
blood serum of pregnant women. It arises, according to Abder- 
halden, as the result of the invasion of the maternal circulation by 
syncytial cells or their products derived from the newly forming 
placenta. 
Ever since the discovery of the existence of such special internal 
secretions as hormones and chalones doubtless every biologist has 
thought of the possibility and many have expressed the idea that 
such substances might be concerned in some way in transmitting 
the results of somatic modifications to the germ, although, to 
our knowledge, no one has yet supplied a plausible explanation of 
how somatogenic are converted into blastogenic modifications by 
such means. We feel that our results may throw some light 
upon the possible existence of such a mechanism, though we do 
not intend to enter into this aspect of our subject at the present 
time. We may, however, discuss the question in greater detail 
in a subsequent paper. 
As matters now stand, we do not feel impelled to insist on 
either interpretation of the mode of inheritance, still less are we 
inclined to undertake any categorical exposition of the serologi- 
cal detail. We are more interested in presenting the facts that 
our experiments have revealed. 
