LIFE-HISTORY AND HABITS OF TERRESTRIAL ISOPODA 303 



For upwards of two years I kept specimens oi Platyarthrus 

 hoffinannseggii, Brandt, in an ants' nest made between two 

 sheets of glass, as recommended by the late Lord Avebury. 

 During the greater part of the time they occupied a special 

 portion of the nest, and seldom left it. So far as could be 

 ascertained by careful observation, they did not feed upon 

 the dead ants. From time to time a fungus appeared and 

 also an alga, both of which I believe they fed upon. The 

 excrement of the ants seemed to form the chief food. There 

 were about eighty ants in the nest. One of the woodlice 

 died about nine months after stocking the nest, and was 

 devoured by its relations. No breeding took place. 



On 2 1st March 19 14 two examples of Porcellio scaber, 

 Latr., were placed upon a broken piece of a flower-pot in 

 a petri dish to which a little moisture was added. For some 

 days the faeces were noticed, but these became fewer and 

 fewer and ceased about the twelfth day. The dish was 

 regularly cleaned out and moisture only added. One 

 specimen moulted on 13th April and the other one died on 

 1 8th April. The remaining specimen lived and continued 

 active until 23rd May, or for sixty-four days after its last 

 meal. 



Hibernation. — Strictly speaking, none of the species 

 occurring in the British Isles hibernate, but I am informed 

 that the same species in the United States are found, during 

 the winter, in the burrows of earthworms, and when dug up 

 appear distinctly torpid, and that it is only after some little 

 time that they commence to move about. 



In this country, on the approach of winter, many of the 

 commoner species make their way into outhouses or into the 

 refuse around manure heaps. This is particularly so in the 

 case of Porcellio scaber, Latr., and Oniscns asellus, Linn. ; 

 Armadillidiuni vulgare, Latr., on the other hand, remains 

 at the roots of plants, seven and eight inches below the 

 surface, tightly rolled up all through the winter. The earliest 

 record I have for a specimen on the surface is 12th April. 



Messrs Webb and Sillem ^ record an interesting 

 observation made by Mr John W. Odell in connection with 

 ^ Webb and Sillem, The British Woodlice^ London, 1906. 



