ECOLOGICAL SUCCESSION. 2Q 



mouth ot hypothetical stage D, ecologically similar to that m>\v 

 found at the point- v Thi- i- represented by the three daces 

 and the Johnny darter. 



As the hypothetical stage D eroded its bed and became >tage 

 K, which i- n .u-d by County Line Creek, ti-h community 



1 wa- succeeded by a ti-h community ecologically similar to 

 iln- ti-h community no\\- pn--ent at points 4. This is eco- 

 .illy rrpre-ciited by the three daces, the Johnny darter and 

 the \oiin- ot tin common -ticker. The fir- h communitie- di 

 nated as I, 2. and ; had meanwhile mo\ed inland and \\ 

 arranged in tin- order which their ec, .logical eon-titution required. 



Tin- continuation of the process iv-uhed in di-placin- a li-h 

 <omimmit\ ecologicall) -imilar to the ti>h o.nnnuinity 4 b\ a 

 !i-h communii\- . . all\ -imilar to the ]ire-ent ti>h i-ommunit\- 



5. Thi> i> repre-ciited in the lower \\ater- <!' Hull Creek by the 

 bluiit-iio- ( -d minnou .ind the little pickerel. HetWe the de-trilC- 



ti,'ii oi its lower course r-tiibi. ' eek should have contained 



ihi- coiiiiiuinit\ and represei 1 



I ' . cal succession is one of the few biological fields in which 



]m-di(tioii i-, p..-~iMc. \\',- m .,\ r.in-y thi> di-cu ii.n a little 

 tmiliri. \\ e ha\e iiotnl that the dt-\elopiu. . .ntinue 



to erode their bid-. ^io\\ lar^i-r. and briiu down the surface , .( 

 the land. The-e ] - h.i\t- not -topju-d in Hull Ctvi-k; it 



\\ill bet mile la; -ntain a larger \olume of water at the 



! .tlit\ 5, and tin- !i-h commiinit\ o| l.ieality 5 \\ ill be -IK <- d< d 

 b\ a li>h coinimmit\ t -i o|, ,^ie.ill\ -imilar to that now at locality 

 I ;ire-ented b\ the -unti-h and ba-- pn -< in. 



Thi e ha- been d. -unated a- In | n.t lietic.il G in the 



diagram, \\ith a further continuation of the process, the li-h 

 iimillit> of - g< ( ,. ' . ' 6, \\ill be succeeded b\ a ti-h 

 community eo>l( . Really -imilar to that now found at the locality 

 7 Hull Creek-Dead Ki\n-. Sta^e 11 . The ti-h are -ho\\ii iii 

 column 7, Table I . 



.U<7/.'<></ and 



The di-cu ion ab..\e i- intended to illu-tratc a method of 

 analysis as well as to ill u-t rale the principle- in\ol\vd. In order 

 to make both clear, more ti-h communities ha\ e been noted than 



