ABSTRACT
The water content of Lumbricus terrestris, after keeping on moist filter-paper for 3 or 4 days, is 84-8 % of its body weight. That of Allolobophora chlorotica is 80 % of its body weight. Both species can survive a loss of 60 % of the body weight, but not much more.
Earthworms of the species A. chlorotica, A. terrestris f. longa, Dendrobaena subrubicunda, L. rubellus and L. terrestris are all able to survive from 31 to 50 weeks in soil totally submerged beneath aerated water. The same species, and A. caliginosa can survive for 72-137 days in aerated tap water without food.
Garden specimens of A. chlorotica make U-shaped burrows in soil beneath water. They do not irrigate either the burrows or glass tubes. Egg-cocoons of A. chlorotica, taken from culture pots of soil, will hatch under water and the young worms will feed and grow though totally immersed.
D. subrubicunda, L. rubellus and L. terrestris avoid immersion in water when allowed a choice between water-saturated and moist but air-filled soil. When A. caligmosa, A. chlorotica and A. terrestris f. longa are allowed a similar choice, a small proportion of the population is always found in the water-filled soil.
Enforced submergence before being allowed a choice of environment does not affect the behaviour of L. rubellus, i.e. water is still avoided. Similar treatment of A. chlorotica and L. terrestris results in a more frequent choice of water.
It is unnecessary to postulate that the individuals of A. chlorotica occurring in Lake Windermere constitute a ‘biological race’.
The avoiding reaction of earthworms to immersion may explain why they leave the soil after heavy rain.
