320 NOTES AND COMMENT 



Forest Service. He has constructed a calendar of the leafing, flower- 

 ing and seeding of some 72 trees of the eastern United States. These 

 results are presented in a diagrammatic form, and in such a manner 

 as to show the dates of a given activity in the northern and southern 

 portions of the range of a tree, without, however, showing the dura- 

 tion of any of the activities. The sources of information and the con- 

 ventions of the chart are fully discussed and a bibliography of tree 

 phenology for the eastern United States is appended. 



The heavily forested portions of equatorial Africa form a rela- 

 tively small percentage of the whole area of that continent. It is 

 the contention of Captain C. H. Stigand, writing in the Geographical 

 Journal (June, 1915), that the primitive agricultural methods of the 

 natives are responsible for a great reduction in the area of forest. 

 The fertility of newly cleared land and the rapid loss of this fertility 

 under cultivation are responsible for continuous encroachments on the 

 forest. The abandoned fields are occupied by grass and bush and are 

 apparently unable to revert to forest so long as the forest front con- 

 tinues to be attacked. Several lines of evidence are adduced by Cap- 

 tain Stigand to show that extensive arsas of forest have disappeared, 

 probably during the last 600 years, in British East Africa, in Uganda, 

 and in the northern portion of the Congo. 



At the Philadelphia meeting of the American Association a group 

 of men interested in ecology met informally to consider the advisability 

 of organizing an American Ecological Society. The principal incen- 

 tives toward the formation of such a society are the desire of animal 

 and plant ecologists to have greater contact and the urgent need of 

 summer field meetings. A committee was appointed to prepare a 

 scheme of organization and to call a meeting of all ecologists inter- 

 ested in the proposed society, to be held in Columbus during convoca- 

 tion week in December of the present year. Those who are interested 

 in the society but do not expect to attend the Columbus meeting- 

 should communicate with the Secretary of the organization commit- 

 tee. Dr. H. C. Cowles, University of Chicago, Chicago, Illinios. 



