56 



pamphlets, all of which are catalogued to date by titles of arti- 

 cles and by authors' names. 



It has been the general purpose of the natural history survey, 

 first, to work up those parts of the zoology and the cryptogamic 

 botany of the state which are least likely to be studied 

 thoroughly by other public agencies or by private investigators, 

 publishing the results of these studies froan time to time in 

 special bulletin articles ; and, second, to present comprehensive 

 summaries of knowledge in each department of the zoology 

 and botany of the state in the form of final reports. As the 

 continued maintenance of the survey seemed for many years 

 precarious, under the conditions then existing, its funds were 

 for a long time used principally for the accumulation of mate- 

 rial, and this has gone on far in advance of studies for publica- 

 tion. Highly valuable collections have been made, for example, 

 from Lake ^Michigan, from the northern lakes of Illinois, and 

 from the waters of the state at large, which have never yet 

 been studied and reported on. 



The controlling idea in the management and development of 

 the survey is expressed in the introduction to the first volume 

 of its reports, written by its director — the present writer — 

 in 1889, four years after its legal establishment as the recog- 

 nized agency of the state for the performance of this work. 

 "Neglecting the flowering plants, and the classification and 

 description of birds and mammals," says this report, "already 

 fairly well studied for this region, we have paid particular 

 attention, so far as descriptive work is concerned, to the lower 

 ]>lants, to reptiles, amphibians, and fishes, and to insects and 

 aquatic invertebrates. Still greater prominence has been given 

 to a general research on the system of actions and reactions 

 occurring within the assemblage of living forms native to 

 Illinois, with a view to exhibiting the laws of interaction and 

 coordination by which the innumerable host and vast variety 

 of the plants and animals of our region arc held together as a 

 definitely organized, living whole. 



"In the preparation of the volumes of this rc])ort it will be 

 our main final ol)jcct to furnish the materials for a full and 



