A. B. Strout 121 | 
Salicaria) and mid-season self-fertility (in Brassica pekinensis) but 
from the evidence at hand these seem to be characteristic of certain 
individuals rather than a condition regularly present in the species. 
Such partial variations may be regarded as reversion to the more 
primitive condition. They exist along with other wide variations in 
the degree to which self-compatibility operates. 
Not only is there variation in the number of sex organs that function 
together, but there appears to be considerable variation as to the stage 
to which processes of fertilization proceed, andealso even in the vigour 
of the seed from fertilizations that are successful. Observations by many 
investigators confirm the fact that in some cases the pollen tubes make 
such feeble growth that fusion of gametes is not possible (see especially 
the recent account by East and Park,.1918). In the case of feebly 
self-fertile plants (chicory, California poppy, and perhaps the apple, 
show this very well) many poorly developed seeds stand as intermediates 
between the few good seeds and the mere rudiments, and suggest that 
some embryo abortion occurring in plants showing feeble one ee 
bility may be due to certain grades of incompatibility. 
As reported above in chicory, occasional plants and certain lines 
appear which exhibit decided degeneracy. One such family of chicory 
has been studied in detail. It showed grades of vegetative degeneracy, 
viability of seeds containing embryos was low, many plants were weak, 
small and short lived and many of those that lived were entirely 
‘impotent in respect to the development of stamens and pistils. Such 
conditions certainly suggest that the poor development of offspring may 
in such cases be an expression of compatibilities between the sex 
elements and may thus closely parallel the conditions of poor vegetative 
and sex vigour observed in certain, though of course not all, hybrids. 
The condition in this one -family of chicory is quite like that reported 
by Darwin (1869, 1877) for the offspring of illegitimate crosses in the 
trimorphic species Lythrum Salicaria. Still it is to be recognized that 
we have no proof that degenerate plants or strains are more frequent 
in species which show self-incompatibility than in those that do not. 
As reported above the heredity of self-compatibility and self-incom- 
patibility has been specially studied in an inbred variety of chicory, and 
this problem had previously been studied (1918 a) in the progeny of 
inter-varietal crosses. The sporadically occurring self-compatible plants 
were made the beginning of selfed lines of descent, which in certain 
lines have been continued for three generations. The results obtained 
during the seven years, during which the self-fertility of over 2,000 as 
