Mat, 1920] PATHOLOGY 235 



1648. Mosley, F. O. Fungoid and insect pests and their control. I. Vegetable and 

 pulse drops. 26 p., 53 fig. F. O. Mosley: Reading, 1918. 



1649. Muller, Kaul. Rebschadlinge und ihre neuzeitliche Bekampfung. [Diseases 

 and insect pests of the grape and modern methods of combating them.j 80S p., 2 pi. (col- 

 ored), 1 map, 65 fig. G. Braun: Karlsrube i. B., 1918.— Abst. in Zeitschr I'fianzenkr. 29: 

 55-56. 1919. 



1650. Nowell, W. The root disease or red ring disease of coconut palms. Agric. News 

 [Barbados] 18: 46. 1919.— Continuation of previous notes (Agric. News 17: 298). Nematode 

 worms found in all stages in diseased roots of Trinidad trees, exactly as in Grenada. Red 

 cylinder in stem, which is a characteristic feature of the disease, was found to be breeding 

 ground of the worm. Bases of leaf stalks may also be affected. Disease spreads from tree 

 to tree but mode of infection remains to be discovered. Important to destroy stems, more 

 so than roots. Name "red ring disease" now considered more appropriate than root dis- 

 ease. — J. S. Dash. 



1651. Nowell, W. Foot rot or mal di gomma on limes. Agric. News [Barbados] 18: 62. 

 1919. — The lime tree in the small West Indian islands is not very subject to this disease. 

 Begins very often in the hollows formed by junction of roots with stem. Exudation of gum 

 generally takes place, followed by drying up or rotting of bark. Regarded as being non- 

 parasitic in origin and brought on by heavy soils, poor drainage and too deep or close 

 planting. Tree surgery followed by use of wood preservative is recommended, the 

 necessary attention being given to cultivation and drainage. — /. S. Dash. 



1652. Pethybridge, George H. A destructive disease of seedling trees of Thuja gigantea 

 Nutt. Quart. Jour. Forest. 13 : 93-97. 1919.— Young larch and Thuja trees growing at the 

 forestry station at Baumreagh, Queen's County, Ireland, were being killed. No fungus was 

 visibly associated with the young larch; investigations of specimens showed, however, that 

 the leaves and twigs were thoroughly permeated with the mycelium of Botrytis. This was, 

 in all probability, the cause of the trouble. — The Thujas were 3 years old, about a foot or less 

 in height, and nearly all quite dead. On the dead leaves small, rounded, flattened, brown- 

 ish black, more or less gelatinous pustules were found in large number. When the diseased 

 material became dry, the pustules became more or less hard or horny in texture. The fungus 

 proved to be Keithia thujina. As far as known, this fungus has not been found elsewhere 

 in the British Isles. Where cases of the disease occur in nurseries the dead and dying young 

 trees should immediately be pulled up and destroyed. — C. R. Tillolson. 



1653. Richter. [Rev. of: Bartos, W. Einige Beobachtungen iiber die Rostkrankheit 

 des Riibenkrautes. (Observations on the rust diseases of beet tops.) Blatter fur Zucker- 

 rubenbau 24:152. 1917.] Biedermann's Zentralbl. Agrikulturchem. 47:263-265. 1918. — 

 The sugar content of beets with sound, leafy tops was 22.02 per cent while that of diseased 

 tops was 21.48 per cent. The sound beets produced about 340 g. of tops each, while the 

 ones affected by rust produced only about 320. The yields of sugar were in the same rela- 

 tion as the weights of tops. Seed of these two types was planted the following year. The 

 difference in the appearance of the two types was visible for some distance, the leaves of the 

 plants affected with rust had a brownish color. The sugar content was 1.5 per cent lower in 

 the beets with diseased tops. — F. M. Schertz. 



1654. Ritzema Bos, J. Bijdrage tot de kennis van de werking der bordeauxsche pap op de 

 aardappleplant. [A contribution to the knowledge of the action of bordeaux mixture on the 

 potato plant.] Tijdschr. Plantenz. 25:77-94. 1919.— It is common knowledge that bor- 

 deaux mixture acts upon the potato plant as well as on the pathogene, Phytophthora in. 

 tans. Its action upon the latter is alone on the germ tube of the conidium or swarmspore 

 due to the solvent action of acid secretions from the protoplasm on the fungicide. — The 

 bordeaux may injure the potato plant through wounds which lay bare the cells beneath the 



