The Relation of Oxygen Consumption to Body Size and to Temperature in the Larvae of Chironomus Riparius Meigen

The oxygen consumption rates of 3rd- and 4th-instar larvae of Chironomus riparius have been measured at 10 and 20° C. using a constant-volume respirometer. The oxygen consumption is approximately proportional to the 0·7 power of the dry weight : it is not proportional to the estimated surface area. This relationship between oxygen consumption and dry weight is the same at 10 and at 20° C. The rate of oxygen consumption at 20° C. is greater than at 10° C. by a factor of 2·6. During growth the percentage of dry matter of 4th-instar larvae increases from 10 to 16 and the specific gravity from 1·030 to 1043. The change in the dry weight/wet weight ratio during the 4th larval instar supports the theory of heterauxesis. At 20° C., ‘summer’ larvae respire faster than ‘winter’ larvae.