摘要:

SUMMARY OF PARTS I AND II1The flora and fauna of the bacteria bed of a sewage plant are described, and their interrelationships discussed.2A definite cycle in the character and quantity of thePhormidium(Cyanophyceae), the main constituent of the surface growth, is described, the most striking feature of the cycle being the spring off‐loading.3The Enchytraeid worm,Lumbricillus lineatusMull., is briefly described and its habits observed in relation to the conditions in the bed. The worms feed primarily on the growth ofPhormidium, and consequently tend to cluster at the surface, when this is abundant and climatic conditions allow. Cold drives them slightly down, but the off‐loading sends them deeply into the bed, when an increased proportion pass out with the effluent. Drying of the surface in summer sends them down in an erratic manner according to the degree of desiccation.4The cause of the off‐loading of the surface growth in spring is its change from a leathery to a spongy condition. The worms are mainly responsible for this and, therefore, for the off‐loading. The alga rapidly re‐forms (3–4 weeks) upon the pebbles, worms migrating into it again when it is sufficiently thick. The absence of an off‐loading in summer when the growth is again spongy is attributed to the higher rate of regeneration owing to increased temperature and sunlight, which lessens the effect of the worm depredations.5The importance ofLumbricillus lineatusin keeping open a bacteria bed and helping to maintain its efficiency is proved by means of experimental beds. Worms introduced into an inefficient bed with solids rapidly accumulating cleared the medium and allowed active nitrification to commence. If the bed is very badly choked and septic, the worms may be unable to carry out this function. It is probable that all the larger scouring organisms abundant in the bed have this property to a greater or lesser extent.6The mechanism of the spring off‐loading is discussed with special reference to the role ofL. lineatusin the Leeds bacteria beds.7The importance of the maintenance of the biological balance by means of the most economic fauna is pointed out.8Finally, the need for more intensive physiological stud

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1939.tb06962.x

出版商:Blackwell Publishing Ltd    

年代:1939

数据来源: WILEY

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1939.tb06963.x

出版商:Blackwell Publishing Ltd    

年代:1939

数据来源: WILEY

摘要:

Withthe close of 1938 theAnnals of Applied Biologycompleted its first 25 volumes, and the occasion appeared to be a suitable one on which to review progress in the Association and its journal.I am indebted to various senior Members who read this account in typescript and pave me the benefit of their greater knowledge and experience.

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1939.tb06964.x

出版商:Blackwell Publishing Ltd    

年代:1939

数据来源: WILEY

摘要:

Handbuch der Pflanzenkrankheiten.Herausgegeben von Prof. Dr O. Appel.Third International Congress of Comparative Pathology, Athens, 1936.Reports, vol. I, part 2. Section of Plant Pathology.The GenusSeptobasidium. By JohnN. Couch.Soilless Growth of Plants.By CarletonEllisand MillerW. Swaney.Plant Growth Substances.By HughNicol.Common British Grasses and Legumes.By J. O. Thomasand L. J. Davies.Plant Ecology.By J. E. Weaverand F. E. Clements.Forest Bibliography to 31st December1933. Compiled and published by the Department of Forestry, University of Oxford.Textbook of Dendrology.By W. M. Harlowand E. S. Habrar.Cryptogamic Botany.By GilbertM. Smith. Vol. I: Algae and Fungi.Evolution. Essays on Aspects of Evolutionary Biology presented to Prof. E. S. Goodrich on his Seventieth Birthday.Edited by G. R.deBeer.Heredity.By A. FranklinShull.

ISSN:0003-4746    

DOI:10.1111/j.1744-7348.1939.tb06965.x

出版商:Blackwell Publishing Ltd    

年代:1939

数据来源: WILEY