MR. A. W. SUTTON ON BRASSICA CROSSES. 341 
and neck perhaps more than the Turnip, but the flesh was white like the 
latter. The flowers were almost as large as those of the Swede, but canary- 
yellow in colour like those of the White-fleshed Turnip or White-fleshed 
Swede. They were abundant and apparently normal, but produced no seed 
although many were pollinated by hand. It was discovered later that the 
pollen was abnormal in form and structure, many of the pollen mother-cells 
having undergone peculiar changes which we hope to investigate further in 
the coming season. 
The very marked sterility and the intermediate character of the plants 
obtained when the Swede (Brassica campestris, L., var. Napo-brassica Rutabaga, 
DC.) and White-fleshed Turnip (Brassica Rapa, L.) are crossed, seem to point 
strongly to the conclusion that they are true hybrids and that the parents are 
specifically distinct. 
Apart from the fact that the plants are sterile, they are so different in 
character from the so-called “hybrid” yellow-fleshed Turnip, that it does not 
appear likely that the latter has originated by crossing the Swede and 
Turnip. 
In addition to the Turnip X Swede cross just described, many others were 
made, including the following, which should probably be placed in this 
group :— 
Colza Rape on Yellow-fleshed Tankard Swede. 
Colza Rape on White-fleshed Round Swede. 
Colza Rape on Yellow-fleshed Turnip. 
White-fleshed Turnip on Colza Rape. | 
White-fleshed Turnip on White-fleshed Round Swede. 
White-fleshed Turnip on Asparagus Kale. 
White-fleshed Turnip on White-fleshed Swede. 
White-fleshed Turnip on Yellow-fleshed Turnip. 
White-fleshed Turnip on Yellow-fleshed Swede. 
Yellow-fleshed Turnip on Colza Rape. 
Yellow-fleshed Turnip on Ragged Jack Kale. 
Yellow-fleshed Turnip on Yellow-fleshed Swede. 
Yellow-fleshed Turnip on Ragged Jack Kale. 
Yellow-fleshed Turnip on White-fleshed Swede. 
Yellow-fleshed Turnip on White-fleshed Turnip. 
Asparagus Kale on Yellow-fleshed Tankard Swede. 
Ragged Jack Kale on Yellow-fleshed Tankard Swede. 
Yellow-fleshed Round Swede оп Ragged Jack Kale. 
From all these crosses hybrid plants were obtained, many of which proved 
sterile, while others unfortunately died off in the winter before the question 
of their fertility or sterility could be ascertained. 
The most interesting of these are shown in figs. 23 to 57 (Pls. 27 to 29). 
