QUANTITY 69 
We note that on the whole the carbonates, CO., and bacteria are 
greater in quantity according to age. Oxygen is on the whole less. 
TABLE VII 
SHOWING THE NUMBER OF Entomostraca IN APPROXIMATELY 90 LITERS OF WATER 
Average of 
Body of Water September 3, 4 April 30, 1910 Collections in Relative Age 
Parentheses 
Wrolitakete s. iancc gees 213 2,900 1,556 (3) 4 
Praine Pond Ti. 5... 25.. 232 9,333 4,781 (3) 3 
Prairie Fond Ii 2-... -. 4,115 19,866 II,991 (3) 14 
Aug. 28, 1912 
EXO) 0% 6 bit dry SoA ote 556 104 874 (6) I 
Bondizer inns: 6 costes SSO ep iilex ia taewlers 927 (6) 7 
ROR ETA a a oe ene TTS 133 2,680 (6) 14 
ONG 6a Obctancre E toke 22 Snes | 1,039 [PP Th serge aye eee 30 
ONUEG OS aie seic.cee mt | 351 | 2,600 saetece 52 
IBOHGESOR s.c/0c ase eke | 2,870 11,400 anys 89 
ONMKO Seen erecta Sari 2,480 seer 95 
TABLE VIII 
SHOWING RATIO OF NUMBER OR QUANTITY OF DIFFERENT ORGANISMS WHEN THE 
Maximum Is too 
Pond Numbers—Ecological Age-Series 
I 7a 14b 
Raotediveretation: 2. can. vce. wnens snes 20 60 100 
LET NTE RUA cc ASL AOU OA OE Te a2 35 100 
RVUs ee IETS gees Ae eee Orne iene ion 80 80 100 
wphaeridde ss. we Be oer he ° 50 100 
Gilledssnarlsteweraset ate ae = eects Mave 20 50° 100 
WRU CORSA IG MRA U Nhs ch ae oF atest ey 10 50 100 
ANTES TOULEE oS tales COLO A RE 50 go 100 
(CORASATEINES S20 Gy Ag ae ea ae ito) 50 100 
RS ECES MINIT Wee nate tiers os S20 cia Mepeees 40 go 100 
TETIGUNG vose-eost BS 6 0 0 BREE aa ee eee oes 100 7 87 
The Entomostraca are rated on the basis of actual count of six col- 
lections. The other figures are estimates (6). - 
Here we note that the number of Entomostraca was greater in the 
older ponds though some irregularities occur, dependent upon the 
amount of rainfall. In rainy seasons the increase with age appears 
almost throughout. 
As we pass from younger to older ponds we note an increase in the 
number of animals, excepting fish. These appear to decrease, probably 
