IMPENDING DEVELOPMENTS IN AGRICULTURAL 



ZOOLOGY. 



By Professor F. W. GAMBLE, F.R.S. 



The endowment of research in Agricultural Zoology by the Develop- 

 ment Commissioners is a sign of the increased interest in the possibilities 

 of the application of this subject to actual practice. Hitherto entomo- 

 logy only has been considered of value in regard to agriculture and 

 though other classes of animals have long been known to exert an impor- 

 tant influence upon the yield of crops and stock, yet no advance has 

 hitherto been made in their study which can compare with that accom- 

 plished in the case of insects. Now however the Board of Agriculture 

 has asked the University of Birmingham to take up these hitherto 

 neglected branches of zoological study with special reference to helmin- 

 thology and a beginning has been made both with this subject and with 

 the protozoology of the soils. 



In the present article I propose to discuss briefly some of the problems 

 that he before the investigators in this latest apphcation of zoology to 

 agriculture. Taking first, the organisms of soils (other than insects) 

 the primary impression is the need for an ordered body of systematic 

 knowledge such as entomologists already possess in virtue of the longer 

 study and larger number of devotees which this subject has attracted. 

 There has been up to the present no concerted attempt in any country 

 to determine the biological factors of the soil, their relations to its quali- 

 ties, to seasonal changes, or to its fertihty. Efl^orts have been made at 

 the Rothamsted Laboratory and elsewhere to determine the effects 

 of certain protozoa ; and in Italy a movement for the study of soil 

 organisms is in its inception. But we have at present no estimate 

 based on any but exceedingly small samples, of the animal factors, 

 estimated either qualitatively or quantitatively, that are present in 

 the soil. Dr Russell and Dr Hutchinson have brought forward evidence 

 that the factor hmiting the accumulation of one or more of the essential 

 substances for plant production is a biological and not a chemical one. 



