Tricotyls as Half Races and Intermediate Races. 345 
ous. But hitherto I have not discovered a single in- 
stance of the former, and have only obtained one in- 
stance of the latter. 1 
Before I proceed to a detailed description of my 
races and cultures it seems desirable to give a general 
account of the manner in which tricotylous seedlings 
are found, and how the desired half and intermediate 
races may be most easily derived from them. 
It is well known that amongst the seedlings of dicot- 
ylous species occasionally individuals are found with 
three seed leaves. It is only 
necessary to look over a 
seed-bed in the garden in 
spring in order to find in- 
stances of these. The more 
extensive the sowing and 
the more careful our search 
the greater will be the num- 
ber of tricotylous seedlings 
found. Some species pro- 
duce them in greater, oth- 
Fig. 63. Antirrhinum majus. A, 
C, D, seedlings with 2, 3, and 
4 cotyledons. B, with a deeply 
cleft cotyledon. 
ers in smaller proportions ; 
and they can often be found 
even in the smaller pot-cultures of the greenhouse, but 
in many cases I have had to sow 10,000 or 20,000 seeds 
of a species before finding a single individual which 
showed any variation in this direction. But numerous 
species seem to produce one or several tricotyls in every 
hundred or thousand seedlings. 
1 My Helianthus annuus syncotyleus has not produced a single 
tricotylous plant in the ten years during which I have often counted 
hundreds or even thousands of seedlings every year. On the other 
hand they occasionally occur in Helianthus animus varicgatus and 
some other varieties of the sunflower. 
