150 BROOKLYN BOTANIC GARDEN - MEMOIRS 
Thus plant 2, used as a female, was fertile with pollen from plants 4, 
18, 41, 44 and 52, and sterile with plants 9, 22 and 23; but pollen 
from plant 2 was fertile on plants 1, 3, 4, 5, 7, II, 18, 20, 28 and 29, 
and sterile on plants 9, 10, 13, 25 and 27. It is clear, therefore, that 
instead of the 8 matings on plant 2 that Table I appears to show, 
there are really 21, the 3 reciprocals of course being counted but once. 
These tables were combined for analysis. In the interest of 
economy of space only one is shown, however, since the second can 
easily be made from the first. 
The four exceptions in this huge set of matings are in reality 
negligible. Matings 15 X 44 and 31 X 36 were sterile, though they 
do not belong to the same class. Plant 15 was sterile to 4 plants of 
Class A and fertile to 2 plants of Class B, 3 plants of Class C, and to 
the isolated individuals forming classes D and F. It is unquestionably 
a member of Class A. Plant 44 was sterile to 7 individuals in Class C 
and fertile to 17 plants of Class A, 12 plants of Class B and to the 
singletons forming classes D, E and F. This evidence places it un- 
mistakably as a member of Class C. Plant 31 is also a member of 
Class C as evidenced by 3 sterile matings within that class and by 
fertile matings with t plant of Class A and 3 plants of Class B. Plant 
36 is like plant 15 thrown into Class A by its sterility with 3 others of 
that class, and by its fertility with 3 individuals of Class B, with 2 of 
Class C, and with the lone plant of Class D. In view of this evidence 
and the fact that in these two matings but one pollination was made 
in each case, they are much more likely to be errors of record or of 
technique than true exceptions to our classification. 
The other two exceptions, matings 45 X 18 and 33 X 46, were 
fertile where from the evidence of numerous other matings they should 
have been sterile. Here again but one pollination was made in each 
case; and, coincidence though it may be, each pollination was the last 
mating made on that particular plant. What is more probable than 
that this is a pseudo-fertility appearing during the wane of the flower- 
ing season of the two mother plants, No. 45 and No. 33? 
Six groups appear in Table II, but there is proof of the existence 
of only five. Groups A, B, C, D and F are definitely established. 
Plant 11, on the other hand, is an isolated individual rather than a 
class. It does not belong to groups A, B or C; but unfortunately it 
was not crossed either with Class D (plant 20) or with Class E (plant 
43), hence one cannot say that it does not fall into one or the other of 
these two classes. 
In the three large groups the distribution of individuals is 22, 16 
and 12. About all that can be said about the type of this distribution 
is that the classes are not of equal size. On the other hand, it is 
