6O VICTOR E. SHELFORD. 



on sterile mineral soil or in a filling pond. We have selected the 

 succession of forest animal communities on sterile mineral soil 

 and especially those on sand. 



The forest conditions on the sand areas at the head of Lake 

 Michigan were once among the best in North America for the 

 study of the problems at hand and in spite of the fact that they 

 are rapidly disappearing and have already been destroyed in 

 some of the localities where the data here presented were col- 

 lected, there are still various small areas between Indiana Harbor, 

 Ind., and Sawyer, Mich., which taken together present the chief 

 stages of forest development on sand. There are also localities 

 outside the sand area, in which the later stages are to be found 

 on other soils. 



The searching of older literature, for possible statements which 

 anticipate ideas here presented would require years and has not 

 been undertaken in any adequate fashion as yet. Such antici- 

 pation of ideas and principles is perhaps to be expected but 

 organization and development are just at their beginnings. On the 

 plant side some older literature has been brought to attention. 

 Buff on (1742) discovered that poplars precede oaks and beeches 

 in the development of forest (Cowles, 'n). Cowles found that 

 in the Lake Michigan sand area cottonwoods precede pines, 

 pines precede black oaks, black oaks precede red oaks, red 

 oaks are usually followed by sugar maple and beech (Cowles 

 '99, '01, 'n; Clements, '05; Shantz, '06; Fuller, 'n). We are 

 to present certain representative facts concerning the develop- 

 ment or succession of animal communities, accompanying and 

 contributing to the causes of plant succession. The data pre- 

 sented are by no means complete as only a small part of the total 

 number of animal species that might be collected from such a 

 series of localities, has been studied. However the data are 

 adequate for the purpose of illustrating principles and methods, 

 and of bringing together some of the recent developments in 

 the study of communities of organisms to focus them on the 

 question as to the best method of obtaining and organizing the 

 data of ecology of terrestrial animals. 



