PLANT DISEASES OF CONNECTICUT. 357 
less circular depressed areas of decaying tissue, varying consider- 
ably in size. They are light brown and corky, and are generally 
surrounded by a well-defined purple margin. As the disease 
advances, these patches crack and form deep fissures, which spread 
deeply into the interior of the turnip, ruining it. Numerous 
black dots (pycnidia) now appear on the diseased patches ; these 
dots are cone-shaped, and contain immense numbers of minute 
spores, which emerge from the apices of the fructification in 
small, globular, rose-colored masses. The spores then soon 
separate, and are disseminated by various agencies, especially 
wind.” 
In 1912, Giissow (2) reported the disease from Prince Edward 
Island, Canada, and this seems to be the first report of the dis- 
ease from North America. While we have accepted Rostrup’s 
name for the fungus, we are not sure whether it is distinct 
from a cabbage fungus (Phoma Brassice, or P. oleracea) that 
has caused more or less damage in Europe and was reported in 
Ig11 by Manns (Ohio Agr. Exp. Stat. Bull. 228: 276-89) as 
causing serious injury in Ohio, especially through cankers on 
the stems. The cabbage and turnip both belong to the same 
genus, and so are closely related, and the Phoma fungi found 
on each cause cankers, and have spores about the same size. 
(Manns reports the spores of the cabbage Phoma as 4.5-5y x 
a 
1.7-2p, while those of our turnip Phoma are chiefly 3.6-4.54 x 
1.84). But we do not know whether the spore masses of the 
cabbage Phoma are rose-colored, as are those of the turnip 
Phoma. Manns reports the fungus as occurring on the leaves 
somewhat, and McAlpine reports it on the leaves of cabbage, 
turnip and rape. Johnson has reported a Phoma disease on the 
leaves of Swede turnip in Ireland, and this may be the same 
as our Phoma. The other writers do not distinctly mention the 
Phoma as occurring on the leaves of turnips, though from the 
spraying treatment recommended, it is at least suggested that it 
may occur there. 
While the different investigators have suggested various pre- 
ventive treatments, it is not known yet whether all of these are 
practical, especially the spraying of the foliage in the field. 
Certainly, however, rotation should be practiced where the dis- 
ease has appeared in a field. It is also quite likely that the kind 
and amount of manure used in the field may have some influence. 
