1917] 
FREIBERG—MOSAIC DISEASES 197 
favor the disease and that infection seems to be worse in 
plants growing in moist, clayey soil. There are, however, 
no quantitative data on the water requirements of healthy 
and diseased plants. On studying the weather chart, one can 
BLE II 
METEOROLOGICAL SUMMARY FOR AUGUST, 1916 
TEMPERATURE 
(Degrees Fahrenheit) | Оет инн 
е Ё B (|а: p 
= = ay S HARAC- 
pay PWNS o 
[а 3 EF 8 та 3 Фо DAY 
hl + BS SS g 5 ЯН a 8 © 8 ис 
© | 9 el 81-95“ | ре — 9.9 а 5 Ф 
= Бы спа өзе, |74276 д О 
ЕЕ! Ра! ck. | Zie SEN S IPE 
РЕ 24 24 = Z си 
80 | 72 0|-1 75 62 ‚00 Tis 78 r 
2 2071574. 0| +1 83 71 .34 7.0 49 [|Pt. cloudy 
)4 | 73 | 84 | +5 7 47 .00 | 12. с Clear 
4|96|77|86| +7 81 56 .00 | 13.4 95 |Clear 
5 | 94 | 78 +7 81 58 00 | 14.0 | 100 | Clear 
6 | 93 | 77 + 6 79 48 001 128 92 lear 
7 |94 | 72 -- 4 70 57 .27 9.7 69 | Pt. cloudy 
8 | 87 | 73 )| + 89 69 ‚36 6.8 49 | Pt. cloudy 
9 | 90 | 73 +: 96 77 00 | 12.9 93 1еаг 
0 | 93 | 76 +: 87 64 EY 11.0 79 lear 
)4 | 70 +4 79 62 ‚94 11.6 83 | Pt. cloudy 
2| 9 69 ) | + 95 72 2.10 9. 67 | Pt. cloudy 
3113-62 ) | — 4 98 15 .99 1 ) | Cloudy 
4 | 74| 59 | 66 | —1 100 9 3.67 2 7 |Cloudy 
35 |67 | 7 100 74 1.73 7 57 | Pt. cloudy 
ó | 8: 71 ( 9 76 00 9 67 | Pt. cloudy 
24 | 75 | € + 89 ¢ .00 | 13 99 r 
3 | 9: /8 | + 9 78 5 ‚00 11 86 r 
) | 94 | 80 +10 72 60 ‚00 11.0 81 | Pt. cloudy 
) | 96 | 80 | € +1 "e ay .00 11.9 88 r 
)4 | 77 | 86 | +10 70 59 .00 10 75 r 
УТА Е 0 77 63 T5 511 43 | Pt. cloudy 
ЖЕНЯ. 70 | — 6 74 48 . 00 13.4 100 г 
О 0 67 44 ‚00 13.4 100 | Clear 
38 | 68 | | +: 68 :00-1-: 144. 100 
› | 86 | ‹ у + 85 70 20 5% 4 Pt. cloudy 
1 | е ( — 9 87 1 0. 6 |Cloudy 
НЕ ( —10 74 4 00 | 10. 77 |Pt. cloudy 
2178 | € 70 | — 5 65 - UU 1- 11: 84 | Pt. cloudy 
30 | 83 | с 74 0 68 56 .00 | 11.9 91 | Сіеаг 
31 | 84 | е 7 + 1 71 55 .00 | 10.6 81 | Pt. cloudy 
easily see how the above observation might also be explained 
on the basis of moisture relations, but this is not substan- 
tiated by the experiment next described. 
On January 29, 1917, 6 badly diseased tomato plants were 
