387 
acreage (113.6 acres per mile at the low water of 1901) is little more 
than a third of that which occurs between Chillicothe and the foot of 
Peoria Lake (299.9 acres per mile) ; and is under the rating of any other 
section of the river between Chillicothe and Kampsville.* 
WIDTHS AND Deptus, Foot or PeorrA LAKE TO Pekin, Low Water, 1901 
Miles above Grafton Station witin, ff | ott tt. 
| 
161.9 50 yds. below mouth Farm Cr. 347 8.1 
160.7 |P. & P. U. R.R. bridge....... 915 6.6 
159.9 640 11.8 
159.0 100 yds. below Wesley........ } 402 8.3 
TUE O hes MEER Shee eat Bet Nira ee ME aaneeteerr 514 7.5 
TAO. Weactreterene ere Riasse dieters aiaueiere tayers: fae < 586 Fier 
AON ea A\\\etoustamerstemctes «see semen wrens cs 640 ee 
ELS Ota boy Ol Sh itor et es We teat ance a oees 515 8.5 
153.9 led. etcde perce Ne cere ob cays Rte) wire 439 12.4 
Hi OS Maite Mehbh | taates sy avon eceucitorana init syane setue esos) stlenats 475 10.3 
153.0 Pekin, at wagon bridge....... Stare 11,2 
Bottom Fauna.—The bottom collections made in cross-sections at 
Wesley and Pekin in 1915 included four channel hauls and four hauls 
in the 4-7-foot zone. In neither depth zone was a fauna indicated quite 
so rich as that of the channel and shore zones between Peoria and Chilli- 
cothe, the average channel poundage amounting to 253.8 lbs. per acre, and 
that of the 4-7-foot zones to only 206.3 Ibs. 
Larvae of caddis-flies (principally Hydropsyche sp.) were decidedly 
more abundant in the swifter stretches of channel between Peoria and 
Bottom FAaunsA, CHANNEL, WESLEY TO PEKIN, 1915 
Hike é Small 
Viviparidae : Insects, 
and ! Sie as worms, Total 
Pleuroceridae Sphaeriidae Crustacea 
Number per sq. yard, 
Average 87.7 16.7 129.0 233.4 
4 collec- 
tions 
Pounds per acre, av. 224.6 8.3 20.9 253.8 
4 collec- 
tions 
Per cent. of total, | 
(By weight) 88.6% 3.2% 8.2% 
*See table, p. 378. 
