SECTIONAL TRANSACTIONS.— D. 387 



study of these laws shows that dispersion is due to the more rapid advancement within 

 the Western Palsearctic region of improvements in organisation, this region being the 

 theatre of the highest developments of the various forms of life in the world, and 

 consequently there exists a more or less regular decrease of dominating power and 

 organisation as we proceed therefrom ; and confirms the region as that of the greatest 

 evolutionary force, the forms arising there being superior to those of every other 

 region, and therefore of invading and overrunning the neighbouring territories and 

 dispossessing the previous occupant, and this is shown to be equally true not only for 

 the Mollusca but for Mankind, Birds, Earthworms, Spiders, Plants, Fungi, Diatoms, 

 Desmids, &c, and emphasises the improbability of world-diffusion from the Antarctic 

 or other centres as is sometimes advocated. 



The routes of dispersal from Europe of the dispossessed species have been deter- 

 mined by the correlation of a large number of facts gleaned from many sources, 

 and are shown to be largely influenced by physical features, and that the areas now 

 occupied, considered in relation to the evolutionary area, form an index to their position 

 in the scale of life, as is confirmed by geological evidence and by the distribution of 

 the Mollusca in time and space and supported by that of Mankind, Birds and other 

 organisms displaying the intimate and indissoluble connection with Evolution and 

 Phylogeny. 



Prof. E. E. Prince.— The Pectoral Fin in the Mackerel Sharks ; Skeletal 

 Contrasts in Isurus and Lamna. 



Prof. E. E. Prince. — The Canadian Land-locked Salmon or Ouananiche. 



Dr. J. \V. Munro. — The Xeeds of Economic Entomology. 



With increasing specialisation in agricultural and forest entomology there has 

 been a tendency to regard economic entomology as a branch of plant pathology or 

 of agriculture or forestry and its zoological basis has been neglected. 



While much can be done to control insect outbreaks by improved methods of 

 cultivation, by selection of immuno or relatively immune crop varieties and by such 

 mechanical means as spraying and dusting, there is a real need for work on insects 

 as such. In the solving of many insect problems progress depends on a fuller 

 knowledge of insect morphology and physiology. 



What is needed is a fuller recognition both by zoologists and by growers and 

 manufacturers, who suffer from insect depredations, of the vast field still to be explored 

 in economic entomology and of the varied nature of the work to be done. Economic 

 entomology has need both of those who are interested in industry and the application 

 of science to industry and of those who are interested in research. Until both groups 

 of workers work in harmony progress will be slow, but by co-operation both groups 

 of workers will benefit. It is, however, for the zoologists to show the way. 



Afternoon Excursion to Washburn Valley. 



Exhibits. 

 The Rev. Ur. S. G. Brade-Birks. — Recent Progress in our Study of British 

 Diplopoda (Millipedes) and Chilopoda (Centipedes). 



Millipedes and Centipedes ; especially recent progress in the study of British forms. 



The following subjects are included : — 



(A) Recent contributions of the continental workers Attems, Brolemann, Loh- 

 mander, Schubart, and Verhoeff to our knowledge of groups and forms occurring in 

 the British Isles. 



(i) Attems (1926), ' Progoneata. Chilopoda,' in Handbuch der Zoologie, IV Band 

 (Berlin and Leipzig : Gruyter), reviews the classification of Diplopoda and Chilopoda. 

 The application of his conclusions to British forms is illustrated by specimens and 

 diagrams. 



(ii) Brolemann (1923), ' Blaniulidae,' Arch, de Zool. exp. et gen. 61, 99-453, includes 

 an account of British forms which are exhibited. 



(iii) Lohmander in Sweden and Schubart in Germany have recently thrown light 

 upon certain nomenclatural questions. Their conclusions are illustrated by micro- 

 preparations and other specimens. 



1927 Z 



