Observations on the Oxygen Consumption of Certain Marine Crustacea^ 
P. B. VAN Weel, John E. Randall, and M. Takata^ 
Many papers dealing with the respiration of 
Crustacea with respect to ecological problems 
have appeared (Bull, 1931; Edwards and Irv- 
ing, 1943; van Heerdt, 1940; van Heerdt and 
Krijgsman, 1939; Hyman, 1932; Johnson, 
1936; Munro Fox and Simmonds, 1933; Mun- 
ro Fox and Johnson, 1933, 1934; Peters, 1935; 
Raffy, 1934; Thienemann, 1928), but a num- 
ber of these seem to give results of dubious 
validity. The oxygen consumption has been 
measured under different conditions of tem- 
perature, oxygen tension, etc. More recently 
the effect of carbon dioxide on the oxygen 
consumption has also been studied (Johnson, 
1936; van Heerdt, 1940; van Heerdt and 
Krijgsman, 1939; Schlieper and Peters, 1937; 
Segaar, 1941). However, comparative studies 
using the same method and technique on a 
number of Crustacea from different habitats 
are rare, although the results of such investiga- 
tions would have a positive bearing on eco- 
logical and comparative physiological prob- 
lems. It is well known that many animals, 
living in a special habitat, may show a dis- 
tinct physiological adaptation to that habitat. 
Therefore, the oxygen consumption, at vary- 
ing oxygen tensions, was studied in a number 
of Crustacea from different and specific 
habitats. 
MATERIALS AND METHOD 
The following species were selected: Meto- 
pograpsus messor Forskal, a crab which appar- 
^ Contribution No. 46, Hawaii Marine Laboratory. 
Manuscript received August 4, 1953. 
2 Professor of Zoology and graduate students, re- 
spectively, in the Department of Zoology and Entomol- 
ogy, University of Hawaii, Honolulu, Hawaii. 
ently lives for the most part out of the water; 
Pseudozius caystrus Adams and White, which 
lives underneath rocks in the tidal zone; Phy- 
modius ungulatus Milne Edwards and Platy- 
podia granulosa Riippell, which are found in 
abundance between branches of coral; Pseudo- 
squilla ciliata Miers and Calappa hepatica 
Linn., which live on and in sandy flats rather 
devoid of organic matter (as compared with 
muddy flats) ; Podophthalmus vigil Fabricius, a 
swimming crab found in large numbers on 
and in muddy flats rich in organic matter. 
To determine the oxygen consumption at 
different tensions, each animal was placed in 
a glass tube 20 centimeters long and with an 
inner diameter of 26 millimeters. This tube 
was closed with rubber stoppers through 
which were inserted a glass inlet tube at one 
end, and an outlet tube and a thermometer 
at the other end. Water, containing a known 
quantity of oxygen in solution, flowed from 
a carboy through the tubes. An overflow, 
which gave a constant head of pressure, and 
screw clamps adjusted the flow and kept it at 
a constant rate of 50 cubic centimeters per 
minute (3 liters per hour). Care was taken 
that no air bubbles remained in the whole 
system. Samples of 125 cubic centimeters were 
taken from the in- and outflowing water (5 
minutes "overflow time" was allowed to pre- 
vent errors caused by absorption of oxygen 
from the air) and immediately titrated (Win- 
kler method) to determine the quantity of 
oxygen present. The animals were left in the 
flowing water for at least 30 minutes before 
a sample was taken, whenever water of differ- 
ent oxygen content was used. Control ex- 
periments showed that this period of time 
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