484 
Syncotylous Races. 
other hand, the signification of the pedigree is, in this 
case, quite different from that of the main syncotylous 
race (p. 470). In that case we found a sudden transi- 
tion from 19% to about 98% in the first generation, and 
since then only fluctuation around the obtained value. In 
this instance, however, there was a regular retrogression 
which has reduced the mean value from 90% to about 
50 to 55%. This value corresponds to that of an inter- 
Fig. 101. Helianthus annuus syncotyleus. 1-7, fused cotyl- 
edons, each figure of a single plant; At, atavistic normal 
seed-leaf ; I and 2, simple opposed syncotyls of which 
la represents a transverse section ; 3-4, doubly folded 
syncotyls with 3 peaks; their transverse section in ^a ; 
5. with very slight imagination of the apex ; 6 and 7, 
without imagination ; 6, with one vein and 7, with two. 
mediate race without selection, especially of tricotyls. and 
is about the same as that which was reached by the hemi- 
syncotylous culture (p. 480). There can, however, be 
no doubt that a further selection in the minus direction 
would have reduced the proportion of syncotyls in my 
race to a figure much below this mean. 
We thus see that after a minus selection extending 
over -four Generations, the race still contains individuals 
