RESPIRATION 



89 



animal, smaller individuals respiring faster than large ones, and 

 GlossoscoleXj a larger species, respires at a lower rate than either of 

 the smaller species Pontoscolex or Pheretima (Mendes and Valente, 

 1953). 



Variations in respiratory rate which are correlated with body size 

 are also mentioned by Saroja (1959) working on Megascolex 

 maiinttii. Respiration of this species rises with temperature over a 

 range of 15-35 °C, but the relative rate of increase was greater for 

 small worms (0-15 g) than for large individuals (1-5 g). Qio also 

 shows increases with decreasing weight but no systematic variation 



Table 12 



Rate of Respiration, Before and After Starvation, of Four 

 Typical Oligochaetes 



of Qio with temperature is found. Megascolex maurittii normally 

 lives in a temperature range of 25-30 °C and over this range 

 oxygen uptake shows a linear proportionality to surface area, but 

 at temperatures below 35 °C the ratio oxygen consumption: 

 weight shows a consistent decrease with the rising temperature 

 (Saroja, 1959). 



Gaseous exchange in these tropical earthworms takes place 

 across the body surface as it does in Liimhriciis via the intraepider- 

 mal capillaries. The respiratory rates of Pontoscolex, Pheretima and 

 Glossoscolex all rise when adrenaline (IQ-^ g/1.) is applied to the 



