A. B. Stout 117° 
first few years in my culture plants of this variety ranged from 44 to 64 
feet in height and were quite uniform in general appearance. The 
occasional degenerate plant was always one of the smaller plants. No 
controlled pollinations were made for such plants and they were not 
included with self-incompatible plants. 
It has also been observed that abnormalities may be present in the 
pollen giving grains of noticeably large size. Cytological preparations 
show that these giant pollen grains are due to the incomplete separation 
of the four daughter cells that result from the reduction division. 
Quadripartition is arrested and a spore wall is formed about all four 
daughter nuclei. In some cases the giant grain is -decidedly lobed. 
Such irregularities in the development of pollen have not been observed 
in other stocks (wild, Barbe de Capucin, and hybrid generations) in 
which examination of much pollen has been made. The proportion of 
giant grains has not been large and they have been found in largest 
numbers among highly self-compatible and incompatible plants indis- 
criminately, For many self-incompatible plants, giant grains were 
absent or rare. Thus it would seem that their development has no 
connection with incompatibilities, but is rather associated with the 
conditions of duplication and cohesion which are characteristic of this 
_variety as described elsewhere (1918b). 
The three highly self-compatible plants selected as parents of the J, . 
gave progenies that were decidedly different in regard to vegetative 
vigour and potentiality for seed production, One line of descent was 
decidedly degenerate, the others were highly vigorous in growth and in 
sex vigour. : 
1. A degenerate line of descent. One of the parent plants, R 9 No. 34, 
was 4} feet tall, well branched and exhibited no signs of degeneracy. 
Its main axis was strongly duplicated and there were lesions and con- 
siderable torsion quite as illustrated in a former paper on this type 
fasciation (see No. 9 of Plate XII, 1918b). Giant pollen grains were 
frequent, but the plant was decidedly self-compatible and set abundant 
seed to open pollination. : : 
The series (R 9-3}- ) grown from its seed was noticeably low in 
vegetative vigour. No plant was more than 5} feet tall; few were more 
than 5 feet ; numerous plants were only from 3 to 44 feet in height and 
some were but 2 feet tall. Many plants produced very few seed to open 
pollination and some produced no seed at all. Such impotent plants, 
about 40 in number, were not included in the self-incompatible plants 
recorded for this series. 
Journ, of Gen. rx “4 
