xii 
PAGE 
Profile of a section of the Illinois River. 
Maps of Illinois River and bottom-land lakes, Chillicothe to Grafton, 
with index sheet. 
ARTICLE XVI. AN ECOLOGICAL SURVEY OF.THE PRAIRIE VEGE- 
TATION OF ILLINOIS. BY HOMER SAMPSON. (3 Maps, 30 
PLATES) | AT GUS Ty) UOT sor we sissereisis nie loeis/eisieie c/s elem stele ic/nte e/ece'sfalptnietede tetas 5238-577 
Think, osood deo onto oO ny MoO ODUO SOCOM DOUBUCRODTMGE ha. 523 
Location of existing virgin prairie of the state............ a\e: sueyeateveree 527 
Orizin of Whe prairie DAP tatSiccer «sseeler cfeieretereversioysteie aicre nies = his 529 
Succession of prairie plant associations:— 
iL, "The thy dr arch =sWeceSsiOms) sere aye ces e fie el + els 05 io lata ole te) =] oheje oe(ote 1aneheleteneNetene 532 
@; On the. river” HOod=plaAIns © cases joys 21 ss, x, 59s) 2le le <cspsicyolsieis/o)d wale 532 
b. On the old lake bed of Lake Chicago...................05- 536 
Go In) smorainal “dEpressiOnse ere cis omc =fricllo's b staie ats) oicse mieteladetelsle katte tees 540 
2) "The XCrarchy \SUCCESSIONSG 5 tie. c 05 0-1-5 sievejsicle seein. cieie oe oun ieleie/s ha iaepeneie 543 
a Ony upland elackal sSOu si: ssctevs. cavers assi'sscvaheraisiesseheveroks)<tesaie os eee een 543 
OL OW! BSAB oc ai-s fossa nc yay srie eis seueeey viausta’ olin /o,a (ads axes eiledeioyeUeracols ;»/e lene) aaa 548 
Composition Of pthe) ASSOCIATIONS), 6 cc.sjole clexetsiecel «ine s) eieisisie » ols taetspele trees 552 
The relation of prairie and forest in Illinois..................eeeeeeee 557 
Annotated) Liste OF; ISPECIOS issn syaes cseseis:c, 2) 0) over) dus) dS 'apufaict 5yaecdyo\e:ahaans neatoaeaeeeee 558 
Non fechnicali SUMMA ys. <yeyarcteye!s a) onletayactels iolwiapsi susielsle cleus sia sls scshaeleneteteeets 569 
DLAteraburewCitedis epic sioleserevelcdeisre ssecavessbarssNers-eleressyelelsnes aah sieid oye cree eee 576 
