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THE INSECT AND OTHER INVERTEBRATE FAUNA 

 OF ARABLE LAND AT ROTHAMSTEDi 



By HUBERT M. MORRIS, M.Sc, F.E.S. 



{Entomological Dept., Institute of Plant Pathology, 

 Rothamsted ExperimeMtal Station, Harpenden.) 



(With 7 Text-figures.) 



CONTENTS. 



1 . Description of the area examined 



2. Method of investigation 



3. Soil analyses 



4. Meteorological conditions 

 .'). Occurrence of weeds . 



6. Soil fauna of the manured plot 



7. Census of manured plot 



8. Soil fauna of the control plot 



9. Census of control plot . 



10. Comparison of the faunas of the two plots 



11. Distribution in depth .... 



12. Comparison with soil fauna of pasture land 



13. Relation of soil faima to soil nitrogen . 



14. The function of the invertebrate fauna in the soil 

 Summary .... 

 References .... 



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This investigation was carried out from February 1920, to January 

 1921, with the object of obtaining information as to the species of insects 

 and other invertebrates present in the soil of an arable field. The various 

 species and their relative numbers, the depth at which these organisms 

 occur, and the effect upon them of the application of farmyard manure 

 to the land were the principal points considered. 



I am very much indebted to Dr A. D. Imms for suggestions and 

 advice throughout this investigation. I am also indebted to Miss K. 

 Warington for information regarding the weeds; to Mr G. C. Sawyer for 

 estimating the nitrogen content of several groups; to Mr H. J. Page for 



^ A grant in aid of publication has been made for this communication. 



