Half Races and Half Curves. 27 
a whole series of malformations. Many cultivated plants, 
such as Cyclamen, Pelargonium and Fuchsia, are particu- 
larly productive of such abnormalities. 
The internal factors may either be latent or semi- 
latent. In the former case the characters are either not 
manifested, or only exceptionally, as in the pinnate leaves 
of the red clover (Fig. 46) and as in the numerous 
cases of pitchers which have been found once, or only 
at long intervals, in the same species. In the second case 
they appear more or less regularly, often yearly, and in 
many specimens. For example I have observed the for- 
mation of pitchers on Magnolia obovata in the various 
botanical gardens which I have visited ; and this species 
as well as its near allies bears pitchers with us every 
year. 1 
In both cases these potentialities are heritable. This 
is proved by their frequence in the case of the semi-latent 
characters and rendered extremely probable in that of 
the latent ones by their occasional reappearance. 
Latent arid semi-latent characters constitute what we 
may call the outer range of the forms of a species. The 
inner range of forms consists of the normal characters 
of a species which are exhibited during its normal life 
or are only induced by such common stimuli as w r ounds, 
mutilations, darkness, or the uncovering of subterranean 
organs and so forth. They are part of the innermost 
essence of the species. But the countless latent charac- 
ters belong just as much to the essence of the species, 
especially when they have formed part of the inner range 
in some remote ancestor and are therefore atavistic. And 
it is just this outer range which presents the best indica- 
1 Over de erfelykheid van Synfisen, Bot. Jaarb. d. Gesellsch. Do- 
donaea, Gent, 1895, P- I2 9- In the course of ten years I have observed 
about 100 pitchers on Magnolia. 
