Page 463, line 4, for Zo read zm; line 5, for peculiar zz read peculiar Zo. 
Page 484, in table, transpose Vegetation-poor and Vegetation-rich. 
Page 501, line 1, for show read shown. 
Page 505, last line of table, column 4, for .4 read y. 
Page 510, line 9, add, azd Volk (’03). 
Page 546, line 15 from bottom, after zs read zm the main. 
Page 549, line 1 below heading, page 551, line 1, and page 556, line 3, for (970 
read (97a). 
Page 556, line 7, before ’07 read 'os and. 
Page 560, table, second column, line 4 from bottom, for (’00) read (’oo),; line 6 
from bottom, for /uuzg read Yung; line 16 from bottom, for (’95) read (’97), line 17 
from bottom, for (’99) read (00); line 19 from bottom, for (’95) read (’96). 
Page 584, at head of second column, for 7897 read 7898 ; under remarks, line 4, 
for above read along. 
Pages 597 and 5098, below table, read *Bottom visible. 
Page 598, eighth column, line 7 from bottom, for 0.76 read 0.28. 
Pages 599-603, 606-610, 612, and 613, below table, read *Plankton not collected on 
same date as sample for water analysis. 
Pages 599-613, columns 2-4, meaning of symbols, abbreviations, etc., as follows: 
v. d. = very decided. 
v. m. = very much. 
Decimal in color column=volume 
of standard ammonium chloride 
solution required to develop the 
same tint when diluted to fifty cu- 
-++ = rising river level. 
— = falling river level. 
+ = stationary river level. 
c. = considerable. 
d. = distinct ; decided: 
f 
. = filtered. 
little: bic centimeters with ammonia- 
m. = much. free water and treated with the 
n. f. = not filtered. usual amount of nessler reagent 
s. = slight. 
