4'.) 



reiiriii^f aquatic- insects, and a few small a(|Uaria. This boat was pro- 

 vided witli sleeping- aecnniiiKidations tor tour men. and willi a well-tur- 

 nished kitclieii. 



I have myself exercised a general supervision over the station work, 

 planning and following- its operations as closely as my otliei- responsil)ili- 

 ties wo\ild permit. Mr. Frank Smith. University Instructor in ZoiUogy 

 and Zoiilogical Assistant of the State Laboratory, has been in immediate 

 charge of tlie station since April Ttli. He has been responsible for the exe- 

 cution of the details of the general plan, and for the technical work on 

 aquatic worms. Mr. C. A. Hart, Curator ol' the collections of the State 

 Laboratory, has done the entomological work of the station: Mr. Adolpli 

 Ilempel hhs worked on ]irotozoans and rotifers; Mrs. Dora Smith has 

 served as our microscopic technologist, and has had charge (jf the rooms 

 down town: and ^Nlr. Mewberry, of Havana, has kept the cabin boat with 

 its equipments and done duty as a general assistant. I alsfi had the ser- 

 vices of Mr. Ernest Forbes as general collector for about six weeks of the 

 vacation i)eriod. Extensive collections and studies illustrating theaciuat- 

 ic botany of the station have been made periodically at Havana by 

 Prof. Burrill, Mr. Clinton, Mr. Yeakel and Miss Ayers. of the Cni versify 

 botanical Department. Chemical analysis of the waters from our prin- 

 cipal collecting stations have been made by Prof. Palmer, and steps have 

 been taken to secure a good map of the locality. Miss Lydia M. Hart, 

 artist of the State Laboratory, has been at Havana for natural history 

 drawing, and Assistant Professor Summers, of the Tniviisity Depart- 

 ment of I'hysiology. spent a part of his vacation making a large series of 

 photographs of the station and its surroundings for use in illustrating its 

 report. 



The greater part of our tield work was done on seven regular stations, 

 visited periodically throughout the year: two on the Illinois river, three 

 on Quiver lake, and one each on Phelp's and Thompson s lakes. The 

 river, about live hundred feet wide at low water mark, and at the high- 

 est water not less than four or five miles across, flows rather sluggishly 

 over a muddy bed, with banks usually of mud or clay, peculiar, however. 

 in the vicinity of Havana and for several miles above and below that 

 point, in the fact that the eastern and western shores are strongly con- 

 trasted in character. The former, as already said, is a bank of sand 

 from twenty to sixty feet in height, with but a little mixture of soil, 

 the western border of a sandy plateau which stretches back from the 

 river from twelve to flfteen miles. The face and summit of this slope 

 and a varying extent of country beyond are commonly covered with 

 upland forest trees, largely oak and hickory. At high water mark this 

 bluff forms the immediate bank of the river itself, but as the water 

 recedes a sloping flat is uncovered, sometimes buried to a little depth in 

 sand, but with clay beneath. This flat widens, here and there, into a 

 boggy or somewhat swampy belt or patch, thickly overgrown with un- 

 derbrush and course flowering plants. 



The river runs, in the Havana district, much nearer this bank than 

 the opposite one. so that few of the bottom land lakes lie between it 

 and the sandy bluflf. Where this sand rests on the clay, multitudes 

 ot springs ooze forth, forming trickling rivulets, which frequently unite 

 before they reach the river in streams a few feet across. This water is 

 ot surface origin, being practically the leachings of the sand bed men- 

 tioned. It is remarkably pure, 'cool, and abundant, entirely free from 

 organic matter, and scarcely at all liable to malarial contamination. 



The opposite bank of the river is ordinarily a flat slope of black wood- 

 land soil, making, when moist, a treadierous mud, and springing up, 

 when laid bare, with a dense growth of weeds and grass. This bank is 

 subject to overflow commonly twice a year, in late winter or early spring 

 and again in .June. During these periods of liigh water all the bottom- 

 land lakes are of course submerged, becoming distinguished again from 

 the river itself only after the waters recede— perhaps after an interval of 

 several weeks. Most of these lakes are either abandoned portions of old 



4- F. C. 



