No. 1, October, 1920] PATHOLOGY 33 



233. Federal Horticultural Board, U. S. Dept. Agbic. Quarantine against corn or 

 maize from Mexico. Notice of quarantine, No. 42, with regulations. Serv. and Reg. 

 Announcem. 67. P. 15-17. 1920. [Also issued as unnumbered pamphlet, from Office of the 

 Secretary of Agriculture.] — Maize (grain) from Mexico is prohibited entry into U. S. A. except 

 under regulations, which are stated, and which are designed to prevent introduction of pink 

 bollworm of cotton with it. — D. Reddick. 



234. Federal Horticultural Board, U. S. Dept. Agric. Stocks, cuttings, scions 

 and buds of fruits quarantine. Notice of quarantine No. 44. Serv. and Reg. Announcem. 67. 

 P. 83-34- 1920. [Also issued as unnumbered pamphlet from Office of Secretary of Agricul- 

 ture.] — Vegetative parts of fruits generally are prohibited entry into the United States 

 from Asia, Japan, Philippine Islands, and Oceania, including Australia and New Zealand. 

 The following diseases are mentioned specifically: Japanese apple cankers (Valsa mali and 

 Diaporthe mali), blister blight (Taphrina piri), and rusts {Gymnosporangium koreaense and 

 G. photiniae). — D. Reddick. 



235. Federal Horticultural Board, U. S. Dept. Agric. Sterile packing material for 

 packing of bulbs authorized. Serv. and Reg. Announcem. 67. P. 34-35. 1920. — Plant quar- 

 antine 37, making "freedom from soil, etc." a condition of entry into the United States, is 

 amended to allow the use of subsoil from Japan, dune sand from Holland, coral sand from 

 Bermuda, and ground peat. Official certificates must be used. Such materials are deemed 

 sterile so far as diseases and insects are concerned. — D. Reddick. 



236. Fulton, H. R. Decline of Pseudomonas citri in the soil. Jour. Agric. Res. 19: 

 207-234. 1920. — Tests on many types of soil, including representative ones from the citrus 

 regions, show a very rapid decline of P. citri in all, reaching the vanishing point in 14 days. 

 This decline is retarded slightly by rendering the soil slightly alkaline with lime water, by 

 lowering its temperature, and more decidedly by withholding water or by previous sterilization 

 with steam. The organism persists in limited numbers for over a year in air dry soil but dis- 

 appears promptly on the addition of water. The decline, on the other hand, is hastened by 

 the addition of dilute sulfuric acid or by a moderate increase in temperature. It is more rapid 

 in water than in soil but is prolonged decidedly in sterilized water. The organism easily 

 penetrates the soil to depths of ordinary cultivation but the normal decline seems to occur 

 at such depths. — Certain bacteria found commonly in soils have a marked inhibiting effect 

 on P. citri in culture and probably are concerned with its decline in soil. — Young roots of grape- 

 fruit seedlings are not readily infected except through wounds. — Rigid experimental methods 

 for making the determinations were developed and tested. They are described in detail. — 

 D. Reddick. 



237. Gochenour, W. S., and Hubert Bunyea. The filtration of colloidal substances 

 through bacteria-retaining filters. [Abstract.] Absts. Bact. 4: 2. 1920. — "The technic in- 

 volved in the filtration of raw meat juice is: The meat juice is first cleared of coarser particles 

 by centrifugalization, and is then mixed with a small amount of kieselguhr and again centrif- 

 ugalized. The supernatant fluid is drawn off, mixed with a sufficient amount of kieselguhr 

 to make a paste approximating the consistency of a thin gruel, and poured directly over the 

 filter candle. Best results are obtained by using a minimum amount of vacuum. It is there- 

 fore helpful to place the filter candle upright in a mantle, allowing gravitation to minimize 

 the amount of vacuum necessary to draw the material through the filter candle into the vacuum 

 flask. The filtration process should immediately follow centrifugalization. The finally 

 filtered product is capable of complete coagulation. Milk, hemolized erythrocytes and other 

 colloids can be rapidly filtered by this process." [From authors' absts. of paper read before 

 Soc. Amer. Bact.] — D. Reddick. 



238. Hartwell, Burt L. Thirty-first annual report of the Director of the Rhode Island 

 Agricultural Experiment Station. Bull. Rhode Island State Coll. 14: 57-65. 1919.— See Bot. 

 Absts. 6, Entry 15. 



BOTANICAL ABSTRACTS, VOL. VI, NO. 1 



