NOTES AND ABSTRACTS. 627 



Lemon, Black Pit of. By C. O. Smith (Phytopathology, iii. pp. 

 277-281 ; December 1913 ; fig.). — Spots, firm in texture, and reddish 

 brown or brown to black, appear on the rind of certain varieties of 

 Cahfornian lemons. A thorn stab is usually present in the centre of 

 the spot. A bacillus hitherto undescribed, and now named Bacterium 

 citriputeale, was isolated from the spots and proved capable of 

 reproducing the disease when inoculated into the rind of healthy 

 lemons. — F, J. C. 



Lettuce Drop. By O. F. Burges [U.S.A. Exp. Stn., Flor., Bull. 

 116; 1914). — Lettuce drop can be readily distinguished from any 

 other lettuce disease. The first sign is wilting of one leaf, then more 

 leaves droop, and finally the Vv^hole plant rots. The disease is caused 

 by a fungus Sclerotinia Lihertiana, the parasitic stage of which does 

 not form conidia, but exists as mycelium. Later, black bodies, 

 known as sclerotia are formed, which remain dormant in the soil for 

 some time, and then develop small fruiting bodies, the apothecia one 

 quarter to one third of an inch in diameter. Spores are given off by 

 the apothecia ; these germinate, but must first grow on dead 

 vegetable matter before they can infect fresh lettuce plants. 



Sclerotinia Lihertiana also causes foot-rot of celery, and can also 

 attack cabbages. 



The following treatment is recommended : — 



(1) Remove and burn all plants as soon as they show signs of disease. 



(2) Drench the place where infected plants have stood with 

 Bordeaux mixture 5-5-50 formula, or copper sulphate solution, i lb. 

 to seven gallons of water. 



(3) Do not grow celery or cabbage on land infected with lettuce 

 drop or vice versa. 



(4) Set out only healthy plants.— D. M. C. 



Lime-Sulphur Solution {Agr. Gaz. N.S.W. vol. xxv. pp. 620-622). 

 — Bring into an iron boiler of 67 gallons capacity 53 lb. of freshly burnt 

 quicklime, 100 lb. of flowers of sulphur, and 25 gallons of water, and 

 stir thoroughly. Then add an equal quantity of water and boil 

 briskly for one hour. Hot water is added to replace what is lost by 

 evaporation. For winter spraying add one gallon of this mixture to 

 7 gallons of water ; for summer spraying take one gallon to 28 gallons 

 of water. — S. E. W. 



Lime, The Relative Effect of Oxide and Carbonate on certain 

 Soils. By H. B. Hutchinson and K. MacLennan (Jour. Agr. Sci. vi. 

 pp. 302-321 ; September 1914 ; figs.). — Caustic hme has a double effect 

 on soils. It causes partial sterilization and decomposes some of the 

 soil organic matter. The amount necessary to bring about these 

 changes varies according to the nature of the soil, especially as regards 

 the amount of organic matter present. Carbonate has a less vigorous 

 action. The paper should be consulted for the figures relating to 

 plant growth— F. /. C. 



