482 
Journal of Agricultural Research 
Vol. VII. No. 1 % 
mosaic disease of N . viscosum as in ordinary tobacco plants affected with 
the common form of the mosaic disease (Pis. 35 and 36.) The mosaic 
disease of N, viscosum produces more or less mottling and distortion in 
the blossoms of these plants. The abnormality known as catacorolla, 
however, has never appeared in connection with the disease. 
Table I .—Inoculations made with the expressed sap of scions of N. viscosum grafted 
upon ordinary tobacco ( N. tabacum) 
Number of 
plants 
inoculated 
(Connecticut 
Broadleaf). 
Date of 
inocula¬ 
tions. 
Material used. 
Symptoms of 
mosaic disease 
in scion of 
N. viscosum. 
Results. 
* 
IO 
1915 - 
Dec. 16 
10 16 
10 16 
Sap of scion of N. viscosum 
grafted on mosaic stock of N. 
tabacum several weeks. 
_do. 
Tap water (control). 
None 
do 
All healthy. 
3 mosaic. 
All healthy. 
10 
10 
10 
IO 
IO 
IO 
IO 
IO 
IO 
IO 
IO 
IO 
IO 
IO 
IO 
IO 
1916. 
Jan. 5 
5 
5 
5 
8 
8 
12 
12 
12 
29 
29 
29 
29 
29 
29 
29 
Sap of scion of N.viscosum grafted 
upon mosaic stock of N. taba¬ 
cum till scion was in bloom. 
Sap of stock upon which above 
scion was grafted (symptoms 
in stock severe). 
Sap of scion of N. viscosum 
grafted upon mosaic stock of 
N. tabacum till scion was in 
bloom. 
Tap water (control).. .. 
None 
None. 
Sap of scion of AT. viscosum 
None. 
grafted on stock of N. tabacum 
several weeks. 
Tap water (control)..... 
Sap of scion of N. viscosum 
None. 
grafted several weeks on stock 
of N. tabacum . 
.do. 
... do. 
.....do. 
Sap of scion of N. viscosum 
...do. 
grafted upon stock of N , taba¬ 
cum till scion was in bloom. 
.do. 
...do. 
.....do. 
...do. 
.do... 
... do. 
.do.... 
...do. 
Sap of scion of N. viscosum 
... do. 
grafted upon stock of N . taba¬ 
cum several weeks. 
Tap water and healthy sap. 
7 mosaic. 
10 mosaic, 
2 mosaic. 
All healthy. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Although the species N. viscosum is susceptible to a mosaic disease 
peculiar to itself, this species of Nicotiana appears to be immune to the 
ordinary form of mosaic disease affecting N. tabacum . Likewise, first- 
generation plants of the cross N. tabacum 9 X N. viscosum <? appear to 
be quite as immune from the disease as the species N. viscosum . All 
