ANABIOSIS OF THE EARTHWORM 59 



and it may be that the uncertainty of the results stated by some 

 experimenters depends mostly upon the fact that not all animal- 

 cules lose the same quantity of water by the exsiccation. But 

 it is altogether impossible to determine the percentage of water 

 lost by the exsiccation of anabiotic Tardigrada, Rotatoria, and 

 Nematodes in consequence of the microscopic dimensions of the 

 creatures. 



A casual observation has directed my attention to another 

 object more appropriate for experiments of this kind and show- 

 ing features completely analogous to the anabiotic Tardigrada, 

 Rotatoria, and Nematodes — that is the earthworm. The 

 Lumbricidae are animals also adapted by the nature of their 

 habitat to exsiccation; they live in the uppermost layers of the 

 soil, which are often more or less dry, and the worms must lose 

 water. Evidently they do not lose it in such degree as the moss 

 inhabitants, but, on the other hand, they have a higher organiza- 

 tion, and the loss of the same percentage of water must be for 

 them of more serious consequence. The comparatively large 

 size of earthworms permits a more detailed study of the process 

 of exsiccation and also the determination, with full precision, of 

 the degree of loss of water. 



In the first study concerning the earthworms, made by me 

 in collaboration with my pupil. Miss T. V. Stchepkina (Schmidt 

 and Stchepkina, '16), in the Zoological Laboratory of the Agri- 

 cultural College in Petrograd, we have tried to determine the 

 influence of lower temperatures on earthworms, and we have 

 shown by experiments that the loss of water has no influence on 

 the endurance of earthworms as to low temperature. The 

 normal worms, as well as the partly exsiccated ones, die between 

 — 1.6° and — 2°C. But in studying this question, we discovered 

 that the earthworms show a very great tolerance of loss of water 

 contained in their bodies. 



I give here a table of results obtained in 1916 in these experi- 

 ments (table 1). 



