158 LOTSY AND KUIPER, A-PRELIM. STATEMENT OF THE RESULTS OF MR. 
-subcutaneous tissue of the abdomen or of the wring joints, nor in 
the peritoneum and the surface of the testes was white. 
CUNNINGHAM from his researches draws the conclusion that the 
F, birds taken at first sight as recessives, at least one of them is 
not pure, and therefore segregation is not complete and perfect 
in the gametes as the Mendelian theory assumes. 
The recessive character when it separates is no longer pure but 
is, at any rate in some individuals modified by a slight degree of 
the opposite character. 
CUNNINGHAM then points out that no sexual difference in the F,’s 
has been found to occur in the cross with which be has experi- 
mented nor in crosses with the Silky described by other naturalists. 
Discussing the explanation BATESON and PUNNETT give of their 
results, he also draws our attention to the differences in the degree of 
pigmentation of the skin in Leghorn and Bankiva, the shanks of the 
latter being pigmented while in the Leghorn they are unpigmented. 
The Silky plumage. 
The normal plumage was completely dominant to Silky plumage in 
our F;’s, just as other naturalists found. We only wish to lay stress on 
the fact that we believe to have observed in a few full-grown F5 birds 
transitions between normal and silky-feathers e. g. in 199.1] (table 1) 
and 584.4(table6) birds with a few nearly normal tailfeathers and quills. 
Vulture hock. | 
BATESON (MENDEL’s Principles of Heredity 1913 pg. 35, writes: 
normal size of feathers on the hocks, or tibiotarsal region is do- 
minant to elongation of these feathers to form quills, the Vulture 
hock of fanciers. This is certainly not the case in our crosses. The 
F,’s of Silky X Bankiva are intermediate between the parents in 
relation to the tibiotarsal feathers. These are really much longer in 
F,’s than they are in the Jungle Fowl. The only question, is how 
long they must be to get the name Vulture hock. 
In our breeding notitions we mentioned a „vulture hock” anywhere 
we found the feathers of the tibiotarsal region more or less elongated 
and having another structure than the normal feathers in this region 
possess. In Fo’s there was a great deal of variation in the length 
of the hock-feathers. We cann ’t draw conclusions with certainty 


