ECOLOGICAL SUCCESSION. :S 



In column C we note a number of fishes, twenty -pecies and 

 four doubtful identifications, as against twemy-i\\<> at point \ . 

 in Hickory Creek. Ten of these are the same in the tw<> stream-. 

 Again \\e find larger fi-he- in the large parts of the stream. 



IV. 1)1-' USSION OF THE D.\TA. 



It i- easy to lose on< self in the maze of taxonomic diversity 

 which one find- in a number of streams separated no further 

 than tin- one- con-iden-d ht-n-. \\V are not concerned with 

 taxonomy. Tin- 5U{ i !)- and inference- herein are chielK to 



illn-iraie .1 melhod ot aiial\ -i- and l" -ui^e>t a method of com- 

 bined experimental and field -tudy. It -lionld be borne in mind 

 throughout the di-cii--ion that ecolo-y as an or^ani/ed science 

 i- in much the -am- :n< >rphol- >-\ \\ a- \\ hen it \\ a- in-i < 5- 



\ tO dlSCUSS methods which are now taken for granted. 



I . m^trilniti in t!n~ .V 



\\'e \\ ill i -'ii-ider the IK. rth -In. re streams lir-t. \\\- ha\e in. ted 

 that the\ .ire -iinilar \ < -.u h other in origin, in material- t i-'-lid, 

 in their relation- t-. the lake, and in bein^ for the m-.-l part 

 madi- H|> ot permanent pool- and intermittent ritlle-. An in-; 

 lion of Table I. -ln.\\- that there i- a definite arrangement ot 

 li-he- in the-i- Streams. 1 in tlnini-.re. that there i- a cl-'-c 

 ( -oi Te-pondcin i- betui ell the Upper Colll'-c- of t he di Iterell t -tream> 



in the matter of the ii-he- pn--ent . a- \\ell a- in their arrangement. 



The only -pccie-. the Inn in 1 1 dace, in the youiue-t -iream < '! -n- 



coe Brook) is the same as the species \\hich i- >n;uc^t tin- source 



.// ///c other st' 



Tin-re are - .UK- dittei. i,- - in the fi-h communilii-- o| corre- 

 sponding part- of the dittt rent -tre.im-. but tin -e are probably 

 due to the failure of B -i\eli SDCCieS to i-ntei a ui\eil -iream. 

 One i- -truck \\ith the >imilarity of the corrc-pondin- li-h com- 

 munitie- rather than the ditt.-iein, 



In making a general compari- m. reference to the diagram <.f 

 the map- of the -tream- I ig. J shows that the different jish 

 communities ar together in the smaller -tream-. I-'i;^. l 



-ln.\\- that the -lope of the bed of the voting -tream- i- greater 



