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Phisestok Uriarinre loneiserd Yxe eo ses es es 218 
SEER COU Am es Sens Sener Becta Catcrehs lam ihe, Pius. oe Nise ashe 4 219 
Seasonal fluctuations of Pedalion mirum (Table)............... 220 
‘GaginratinGlney, 4 fy Ge Bale ie Be bc (ol Sea A wea, die See eee Reon ee Pe ear 221 
TB yan NONaaVOVS UN PANO x ake hes eta COSTES. Siete aca e IGE 5 NS GU Revi eg ear REET 221 
Sere ares LIOR A esac I mn Sac cre As aes hate lat Aap a Sum aeeRavey ol es 222 
(CilexGheveertans, cchvaen ‘ont Ea lin er Grau io Piao eka SGN oo eae oC Rec 223 
Cladocera and Hydrographic Fluctuations (Table)............. 223 
ise sc OnE O re SCCICS ire mri owt ah AES ais GN sons Wid la (Si etant foetal» 225 
Tabular statistical data:— 
Bosmina and hydrographic fluctuations...................-. 228 
Seasonal distribution of Chydorus. Average number per m.*..235 
Effect of temperature on numbers of Chydorus...............238 
A typical pulse of Daphnia cucullata. . ate 5 po 
Diaphanosoma population, with data oa lsinaclete ean river 
UES recs ee Se oa oe ais OR. oe SOON Aue a cine nee ceeieae cmon. 248 
NMociarand hydrorraphic chamg@esss gale. gec p< - eas eae 20 
SETAC OG MEE Cotta Saale ae ee de Sharh cst o)c Hc ates etdiewn Sak BS 
DISCiSSIONM Ole SPECIES. scr etn wnks sine eee Oy oie ais ale at ane nei ene 258 
(CxS 1870 SGI I CP Nie tet Po rucaite atari Ah Chae eRe gece On ea pA RE 258 
Copepoda and Hydrographic Changes (Table)................. 260 
Discrisstom: al SPCCiese. sine teh ees tests ae aa tgs Richey ales 261 
Cyclops viridis and Hydrographic Changes (Table)............ QA, 209 
Mimnenss ob Cy clopida Clable)ie cache. 2 fle oli a ws ae 278 
PRAT IOCLAen ares Oe ake aed Foye rae ana Ae MV sv eltehs ke ich Sass ony eee oe 283 
EN TeTC lim Gl Myne epee eny eae rea one mM arte Ror de, eae aanel ce Sue ue enema 283 
ENG eae RR en EEE ey yee gs OE es Maa erat ko Mecee-e Aa eeey 0 eee 283 
Pergo Treg ere” Ree We Se Rn Never a cierw eee care ae ree ea oP 284 
THLESCEre 5:6 ak es Glatt ke Beate ac Sa te ee he a ees ora Cea 284 
PEt eft ied eae dn Paras teas age mes ee eos tan see ute Ria 202 2 aa soco henge: 285 
elestale [yi Gites ee entre RGR ace Pict Sra ae ar henge + nd 2s ses 285 
(DIGOtH SYS See = Serene See ce ee Crete ees Oe SER eng: Sn cae mena nA 285 
RV Iie lcs Ca eee Pe ee Fee Meer eng Wenresh cr Aes. oLAFESE foo soci nee seaapevewes 287 
TELE PCL ARE ER Meee Ny Reve get ia, aie ae occ am Oe 6 etka Senne eve Se 287 
[Lananellinomenmvelirenigne arg Grpettccle Goo, bkevatnerA O's 6 oO cress eres cen 287 
BNP -S AOE, A Rye GRC a Aan ty Cn gh ic ae a ac ne A ee a 288 
IDE SCURESTGYA OLE AS OVC SS. Ma ce Oe oe a ee ee ee Peer 288 
Periodicity in Multiplication of Organisms of Plankton............... 291-311 
Comparison of Plankton Pulses and Lunar Cycle (Table)............296-299 
(Gaseous! Conmbmentsrotm orca Vice te (lbalole)i 0s ae. ease cred. oe cede etn 306 
Relation of Pulses of Chlorophyll-bearing Organisms to Lunar Cycle 
alba byle)h ee rs anne re aed Ere Panache Sos conn « «23 908 
General Considerations on Seasonal Changes.........................912 
Pecenyercooneaycre AanitGila.. aca eee ae cota Poe ae oe ee tk pe OLE 
Organisms per Cubic Meter in Illinois River in 1898 (Table)........... 314-340 
Biblosrapitys... 2. - oS 2 A ie I ee Sins it 6 dl ca aed ARS eR OE 341-354 
ec eae teri) |. gil ooo ah Rte yeoman viet ete he OOD 
