THE MOSAIC DISEASE OE CUCURBITS. O 
On the gourds infection occurred on 12 varieties, including Cucur- 
bita pepo L., Luffa cylindrica Roehm, L. acutangula Roxbg., Lagenaria 
vulgaris Ser., and L. leucantha Rusby. 
Mosaic has also been produced by inoculation on the following 
species: Momordica involucrata E. Meyer, M. charantia L., EcbaUium 
elaterium A. Rich., Benincasa Jiispida Cog., and Trichosanthes 
anguina L. 
The wild species, Micrampelis lobata (Michx.) Greene, is common 
in many parts of the country both as an ornamental vine and grow- 
ing wild and is often diseased. The identity of this disease with 
that on the cucumber as well as with that which occurs on the less 
common wild species, Sicyos angulatus L., has been proved by 
repeated inoculation. 
From data so far collected, the watermelon, citron, and other 
species of Citrullus seem partially resistant to the disease. No 
successful inoculations have been made by the writer on any plants 
of this genus with the exception of the green-seeded citron, Citrullus 
vulgaris Schrad., and watermelons grown in the field have never 
been found infected although often intertwined with mosaic-diseased 
cucurbits. Jagger (19) reported having obtained a single case of 
mosaic on watermelon by inoculation, but was not able to repeat 
such infection. He also noted the disease on the green-seeded 
citron, but not on the red-seeded variety. Freiberg (13), at the 
Missouri Botanical Gardens, also reported mosaic on the citron and 
showed photographs of the disease. 
CROSS-INOCULATIONS TO OTHER PLANTS. 
INOCULATIONS FROM MOSAIC CUCUMBERS TO PLANTS OF OTHER FAMILIES. 
Certain field observations have at times suggested that cucurbit 
mosaic might possibly be transmitted to plants of other families. 
An example of such a case occurred at Madison, Wis., in 1916. 
A few plants of Martynia louisiana "Mill, appeared in one of the 
cucumber plats, the seed having been accidentally included with 
th#t of the cucumber. A large number of the cucumber plants 
became infected with mosaic early in the season, and a few of the 
martjmia plants" also developed a disease of the mosaic type later 
in the summer, the circumstances suggesting a possible transfer- 
ence of the infection from the cucumber. Inoculations were made 
from the mosaic martynia to healthy cucumber plants and also 
from mosaic cucumber to healthy martynia, but all the inoculations 
gave negative results. 
Most of the inoculations from cucumber to plants outside the 
Cucurbitaceae, however, have been with plants known to be subject 
to infectious mosaic diseases, such as tomato, tobacco, bean, petunia, 
and pokeweed (Phytolacca decandra L.), although a few inoculations 
have been made on plants subject to unknown chlorotic diseases. 
