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LOCK : STUDIES IN PLANT RHEEDING 
Only 25 plants were raised in F 2 , viz., 11 (m.p.f.), 6 (p.f.), 
(mi.), 2 (f.), 4 (w). 
But in F g 3 plants from seeds showing (m.p.f.) in F 2 had 
the following offspring 
No. 2 ... 18 (m.p.f.) ... 3 (m.f.)..J 8 (p.f.)... 1 (f.) ... 14 (w.) 
No. 7 ... 48 „ ... 8 „ ... 7 „ ... g „ ... 20 
No. 8 .. 16 „ ... 9 „ ... 1 „ ... 3 „ ... 3 „ 
Total... 82 20 21 9 37 
A proportion which closely approaches that which is 
expected on the above hypothesis. 
The final test of the hypothesis will be to make artificial 
crosses between,*?.^. (f) plants and (w) plants. From certain 
of these crosses all the original types should be obtained/' 
This experiment has not yet been caried out. 
IV.—THE VIEWS OF DE VRIES. 
De Vries has extended the operation of Mendel’s Law to 
a large number of characters belonging to plants of widely 
separated natural orders. In his first paper upon the law of 
segregation of hybrid characters (67) de Vries propounded, 
as a general rule, that the hybrid always shows one only of 
a pair of antagonistic characters, and this in all completeness. 
Dominance, he asserts, is always complete. But this is by 
no means the case, as Correns (11) has well pointed out, and 
as Mendel himself observed in many of the characters of 
peas. In the remainder of his discussion of this class of 
hybrids de Vries follows Mendel closely. 
In a second paper de Vries grouped together Mendel’s 
examples in Hieracium, the false hybrids of Millardet and 
a series of cases discovered by himself in crossing different 
forms of Oenothera and other species, as “ false hybrids ” ; 
* Cf. Cuénot’s experiments described below. 
