44 



XL. H. M. Morris. "Orz a Method of Separating Insects 



and other ArtJiropods from Soil/' Bull. Entom. 



Research, 1922. Vol. XIII. pp. 197-200. 



Describes an apparatus consisting- of a g^alvanized framework 



supporting a graduated series of sieves, which enables arthropods 



to be separated from soil by means of a current of water. 



XLI. H. M. Morris. "The Insect and otJier Invertebrate 

 Fauna of Arable Land at Rothamsted." Annals of 

 Applied Biology, 1922. Vol. IX. pp. 281-305. 



A detailed study of the soil fauna of Broadbalk field, involving 

 a comparison of the invertebrata of plots 2 (dunged) and 3 (un- 

 manured), their distribution in depth, and relative numbers. The 

 main conclusions are that the bulk of the fauna is concentrated in 

 the first three inches of the soil, and that there are on an average 

 15,000,000 invertebrates per acre in plot 2 (receiving farmyard 

 manure annually) and 5,000,000 in plot 3 (unmanured since 1839). 

 The dominant organisms are insects which numbered over 

 7,700,000 in plot 2 and about 2,500,000 in plot 3. The total 

 amount of the nitrogen contained in these organisms works out 

 at 7349.6 gm. (16.2 lbs.) per acre in plot 2 and 3409.2 gm. (7.5 

 lbs.) per acre in plot 3. It is unlikely that there is any appreciable 

 loss of this nitrogen from the soil. The observations show that 

 although the introduction of farmyard manure greatly increases 

 the invertebrate population of the soil, the organisms which 

 exhibit increased numbers are saprophagons and not directly in- 

 jurious to the growing crop. 



XLII. J. G. H. Frew. ''On the Morphology of the Head 

 Capsule and Mouth-parts of Chlorops T.^niopus 

 Meig. {Diptera)." Journal Linn. Society, 1923. 



The head capsule is described and some modifications suggested 

 of the homology of its facial aspect in Cyclorrhapha as put forward 

 by Peterson in 1916. 



The following conclusions are arrived at : — 



The dorsal and lateral borders of the oval depression mark the 

 position of the arms of the epicranial sature. 



All regions of the head dorsal and lateral to the oval depression 

 are derived from the paired sclerites of the head and the frons and 

 clypeus lie within the depression. 



The antennae arise on the vertex. 



The superficial plate of the fulcrum is the clypeus or fronto- 

 clypeus. 



The tormai are the chitinised plates joining the sides of the 

 clypeus to the sides of the basipharynx. 



XLI 1 1. J. C. F. Fryer, R. Stenton, F. Tattersfield, and 

 W. A. Roach. 'M Quantitative Study of the 

 Insecticidal Properties of Derris Elliptica (Tuba 

 Root)." Annals of Applied Biology, 1923. Vol. 

 X. pp. 18-34. 

 Extracts of Derris elliptica are shown to have a high insecti- 

 cidal value, particularly for c:aterpillars. They are not so toxic 

 to aphids. 



