86 
ANNE M. LUTZ 
with small quantities of pollen obtained from the former. 15 chro- 
mosomes were counted in the somatic cells of No. 3500 and 14 in those 
of No. 3814. 320 seeds from 0. lata X 0. Lamarckiana were planted 
at spaced intervals in seed pans, December 12, 1908; 49 of this number 
germinated previous to the time of transplanting in May. Four of 
the young plants died as seedlings and the remainder were classified 
as follows: 
Table II 
O. lata No. 3500 X 0. Lamarckiana No. 3814 
0. Lavi- 
arckiana 
0. aber- 
rans 
0. lata 
0. albida 
Type 5432 
Totals 
I A chromosomes 
14+1 
15 " 
15 
I 
27 
I 
I 
15 
I 
28 
I 
On December 11, 1908, the same number of seeds from the second 
cross (0. Lamarckiana X 0. lata) were planted in the same manner 
as the above. Only 18 germinated; therefore, on Februa.ry i, 1909, 
119 seeds from the same capsules as the preceding were planted and 
58 seedlings obtained previous to the middle of May. The 76 plants 
derived from this cross were classified as follows: 
Table III 
O. Lamarckiana No. 3814 X 0. lata No. 3500 
0. Lam- 
arckiana 
0. nanella 
Type 3514 
(modified 
rubrhier- 
vis?) 
0. lata 
0. bipar- 
tita {?) 26 
Totals 
14 chromosomes 
15 " 
63 
I 
9 
2 
73 
3 
From these tables we see that in the time allowed for germination, 
almost twice as many 15- as 14-chromosome offspring were derived 
from 0. lata X 0. Lamarckiana, while only 3, possibly only i, of the 
76 plants derived from 0. Lamarckiana X 0. lata had 15 chromosomes. 
Since one or more 15-chromosome mutants usually are found in 
Lamarckiana cultures of this size, it is probable that the 15-chromosome 
offspring of 0. Lamarckiana X 0. lata resulted from 9 8 + c?" 7 and 
26 The identification of these supposed bipartitas was based upon the characters 
of the greenhouse rosettes, as the plants were not transferred to the garden. 
