334 
TABLE I—continued. 
ORGANISMS PER CuBIC METER IN PLANKTON OF ILLINOIS RIVER IN 1898. 
(An asterisk at head of column indicates that all entries in it are based on 
filter-paper collections.) 












(Syoyiey Teyleieic) (efeve) 
| 
8 
3 RS 3 Polyartha platyptera 
Con 
Ss 8 as) ST Bi 8 &§ Male eggs 
1898 38 82 | = Se | Ses Ba 
BS Q8 os e8 8.8 § SES 
TS 33 => SS | SSR 2s ; 
Ss 8 Ss 8 Ss ss S Ss © q Free Carried 
Janeen ae: 0 0 0 0 0 1,000 0 
a) eee 0 0 0 100 0 1,200 0 
Seg WO Spee ae 0 0 0 0 0 11,997 0 
Os Because 0) 0 0 0 24 3,200 0 
‘cies ares 0 0 0 0 240 2,000 0 
Cy er oe 0. 0 0 0 80 1,600 0 
CO) Ate tae 0) 0 0 0 0 6,318 0 
Man, lc casas. 400 | 0 0 0 800 3,200 0 
SO 5 Bice 0) 0 0 0} 1,200 5,200 0 
SSAC ee 0 0 0 0} 6,400 22,200 0 
eee 0 400 0 0} 10,800 37,600 0 1,600 
LO DIGGS an 0 0 0 0 200 40,400 0 2,600 
prado Aas 0 0 100 0 300 42,800 1,300 2,800 
iad yee ae 0 100 100 0 0 26,700 900 1,900 
2 Oe 0} 400; 400 0 0 148,200 8,800 1,600 
OY as re 0 0 0 0 0 696,000 150,400 53,800 
May 3...... 0 0 0 0) 0 582,400 0 19,200 
GS SHO eee 0 0 0 0 0 137,600 4,800 0 
SLAC eWeek 0} 300 0 0 0 195,200 12,000 2,400 
CU Are ee a ) 0} 200/ 800 0 52,200 0 0 
HOD i eee 0) 0} 200] 400 0 52,400 200 0 
Wee Poocsac 0 0 0 0 0 304,000 1,600 0 
eV oe eae 0 0 0 0 0 432,800 0 0 
LO [aera 19,200} g00 0 0 0 241,600 0 0 
See SI ie te 11,200} 800 0 0 0 56,800 0 a) 
icity BSooscee 2,000 0 0 0 0 6,400 0 0 
OEE acet 1,600 0 0 0 0 21,600 0 0 
See mings 7,200 0} 800 0 0 89,200 0 0 
he) Oe 4,000 0} 800 0 0 86,400 0 0 
INGE, Bo once 15,200 0 0 0 0 288 ,000 0 0 
OS ae 4,000 0) 0 0 0 55,200 0 0 
COS Etta BE 5,600 0 0 0 0 84,800 0 0 
CU Oke beet se. 5,600 0 0 0 0 96,000 0 0 
cl Oe 300 0 0 0 0 51,200 0 0 
Sepes Osea: 0 0 0 0 0 4,000 0 0 
TaD fe ee 2,500 0 0 0 0 31,000 0 0 
sD Oe ae 1,500 0 0 500 0 72,500 0 0 
OUD Pei aee 4,800 0 0 0 0 238,400 0 1,600 
Oct eee 1,000 0 0 0 0 24,500 0 0 
lal a aes 0 0 0 0 0 47,500 5,000 500 
Ca ane te 0 0 0 0 0 27,000 2,000 1,500 
eS eae 0 0 0 0 0 37,500 0 2,000 
Won iloceore 60 0 0 0 0 500 0 0 
Cy Sat ee 0 0 0 0 0 1,000 0 0 
SONG ie see ae 0 0 0 0 0 2,000 0 0 
cca? Ne Ge 400 0 0 0 0 6,000 0 0 
SUMED OMe SS 0 0 0 0 0 1,000 0 0 
Dec pore ae 0 0 0 0 0 6,020 0 160 
ae 0 0 0 a) 0 42,100 100 100 
BN Ns shan 0] 200 0 0 40 63,400 0 200 
So) 57h Man te 0 0 0 ) 0 19,200 0 0 
Average...... 1,674 | 67 | 50 37 | 388 | 86,674 | 3,598 1,768 





