TRANSMISSION OF ACQUIRED CHARACTERS. 213 
route from the egg to the complete animal.” This process 
of obscuring and shortening is determined by the law of 
abridged transmission, and I mention it here specially be- 
cause it is of great importance for the understanding of 
embryology, and because it explains the fact, at first so 
strange, that the whole series of forms which our ancestors 
have passed through in their gradual development are no 
longer visible in the series of forms of our own individual 
development from the egg. 
Opposed to the laws of the conservative transmission, 
hitherto discussed, are the phenomena of the transmission of 
the second series, that is, the laws of progressive transmis- 
sion by inheritance. As already mentioned, they depend 
upon the fact that the organism transmits to its descendants 
not only those qualities which it has inherited from its own 
ancestors, but also a number of those individual qualities 
which it has acquired during its own lifetime. Adaptation 
is here seen to be connected with transmission by inherit- 
ance (Gen. Morph. ii 186). 
At the head of these important phenomena of progressive 
transmission, we may mention the law of adapted or ac- 
quired transmission. In reality it asserts nothing more 
than what I have said above, that in certain circumstances 
the organism is capable of transmitting to its descendants 
all the qualities which it has acquired during its own life 
by adaptation. This phenomenon, of course, shows itself 
most distinctly when the newly acquired peculiarity pro- 
duces any considerable change in the inherited form. This 
is the case in the examples I mentioned in the preceding 
chapter as to transmission in general, in the case of the men 
with six fingers and toes, the porcupine men, copper beeches, 
