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Representative character of/ournidadtar..\. css seems ce eee eens oe cee 543 
Predominantly higher production in backwaters.................4. 543 
Causes of periods of low production in backwaters ................ 544 
Summary of statistics of channel and backwater production........ 544 
Indigenous) planktonvof chann eclenseenieeninien sales eee eiaecveneereciele 545 
General: Summary asi! Sekt we nero aeons era See cee lee 546 
Totali-annual' production®. ctr ea ceases ee eee eer 547 
At lava a: cies sis aalaseie-s se cies eee Su ae nei ote aetoeesforcie ls eae pete 547 
At mouth’ obrivienti.c2 si sere eae ec eerie meee eis eee tae 548 
Variation ‘from iy ear'to years. was asmtos eee beeen hss eso ee 548 
Total annual loss of organic matter from Illinois River.............. 549 
Determination of total production as affected by leakage through silk 
5 EON Sore MEANIN EOS BO apOn Dagon a dana CORaoroa ees Se 549 
Volumetric determination by means of filter-paper catches.......... p 
Gharacter of silt iin theseicatchesererrenci1se eerie si aire 550 
Filter-paper catches not suited for volumetric work................ 540 
Confirmation of my results by the work of Lohmann ............... 550 
Methods of making filter-paper catches....................00000-- 551 
Statistical data of silk and filter-paper catches...................... 552 
INASP adnonopApaenos oo on aoc Too Koco dNeosUoe HAR oNdesabIseSbooRORS 554 
Seasonal changesiim ratios norco eee eects eee rector ee 555 
Volumetric methods imperfect as a test of productivity.............. 556 
Comparison with other bodies of water..................-.2.22..+-000 556 
Atbsencerof, comparable (datate- ermree nm ene ee crenelaniet islet 557 
Comparison) with Danube (Steven) ener cter eee tl amiss nt eet 557 
Comparison with New England streams (Whipple).................. 557 
Gomparison with, Elbe y(Seborben) ite eyercteeterayatetelat-eeetteue eres tceleraletel ete 558 
Comparison with Oder (Zimmer and Schreeder)............-...-..--- 558 
Omission of comparisons with lakes............ 0.2.0.2. eeee cess aces 558 
Does geographical position determine planktograph?................ 559 
Comparison of maximum production..............+++.1+ seer eee eee 559 
Statistical datas 2... cin stein rsecie aise nus emia ieee eetetetere Peete ere 560 
Relative productivity of Illinois waters..........+. esses eees eeeess 560 
Location of Seasonal masiimalystayey-my etter te sie ene eile fenetelaletalieleteiep=tal=tere 561 
EECONOMUGIN GONSTACTOLLONS viel tnteiatel fete eee eee eee ere 561 
Illinois River as a source of wealth.... 0.0.0.0. eee cee cece eee ee eee ees 561 
Value for sportand recreation> cy eccee ein erat eten acme 561 
Are resources now utilized to advantage?................ 0-0 e--e ease 562 
Relation of plankton to fisheries..........2..2-..0 2 0- ce ee een eee ers 563 
ING Tools bovis es) Neo abnahoinade Hoounesh oo tuoore asc ubes SoUade mabe 563 
Importance of knowledge of plankton in scientific aquiculture........ 564 
Comparison of annual product of fisheries and plankton............... 505 
Smale UGC inan a Hone pareipeaop boosts uec conoccdonsonb aspnpenacane 565 
Gorrespondence inidatals nq science rue ee nein ey etree cree 566 
Annual wastage and fish production ............ 61+ eeeeee cere eeee ee 567 
Suggestions for utilization of resources.....-..-... 0... -.e+seeeeeeeee 567 
NEON GLUSTIONS ii ites cfeietsie ie =) sreswie: ennai chal cole eltes fal ey Neate teks lassie otaoletstarelintotele 569-574 
f BG oCh ORE oon cern TOD aaron Anse qos adatkinod LOntapameoeo 575-618 
BIBLIOGRAPHY........ SAO OtoaenAc cdg Aona bose aaa dnbaar ",... 619-624 
EXPLANA TIONIO“ PLATES: sae. + cchcelcrer isomer tateteh tier ralelete sete ance aiaetats 625-628 
