1G0 
president’s ADDRESS — SECTION D. 
The members of the cryptozoic fauna [have been derived from 
nearly ail the principal groups of the animal kingdom, and the only 
character which they all possess in common is their hatred of exposure. 
The darkness or semi-darkness in which they live, however, does not 
seem to have had any influence upon the eyes of cryptozoic animals. 
In this respect they differ markedly from many animals which dwell 
in dark places— such as the inhabitants of caves, some burrowing 
animals, some deep-sea forms, and the remarkable blind Crustacea 
found inhabiting the subterranean waters of New Zealand, and so 
admirably described by Dr. Chilton* The cryptozoic animals appear 
to avoid the light by choice and of their own free will, and there can 
be no doubt that their eves are of actual service to them in dis- 
tinguishing between light and dark plaees, and in perceiving when it 
is dark enough for them to safely venture forth from their hiding- 
places in search of food. One of the most striking and often annoy- 
ing facts which confronts the field naturalist in search of cryptozoic 
animals is the rapidity with which inany of them disappear again into 
.lark crevices as soon as their cover is removed. 
Some forms evidently prefer one kind of cryptozoic haunt to 
another. In the South Island of New Zealand, for example, l have 
found numerous specimens of a large Chelifir beneath stones, while I 
never observed them under fallen logs, which were abundant in the 
immediate vicinity. The choice, is probably determined in some cases 
bv questions of food supply, and in others by questions of temperature 
or moisture. Other forms occur apparently indiscriminately under 
lo^s or stones, as, for example, the larger Victorian Peripatus and 
the Australian Land Nemertine ( Geonemcries nustr aliensix) , the mam 
objects to he secured being evidently darkness and moisture. 
Divers causes have probably impelled different members of the 
cryptozoic fauna to adopt their peculiar mode of life. A large pro- 
pci tion of them are doubtless to be looked upon as refugees but, 
while some seek protection from living enemies and competitors, 
others do so quite as much on account, of their delicate organisation 
being unable to stand exposure to the light and heat of day. “ Drying 
up' 7 is fatal to many cryptozoic animals, and especially to those which 
beloim to typically' aquatic groups, such as the jSTemer tines and Land 
Planarians, which, as collectors know to their cost, dry up very rapidly 
when removed from their native haunts, unless care be taken to supply 
them with abundant moisture. Nor is moisture alone all that is 
requisite for their welfare. The question of temperature is likewise 
of vital importance, at any rate in the case of Land Planarians, which, 
even when supplied with’ abundant moisture, rapidly perish and dis- 
integrate into a liquid, evil-smelling mass, unless they be caretully 
kept cool. 
Other cryptozoic animals are doubtless attracted by the presence 
of some special food, supply which flourishes in their dark retreats. 
Decaying logs, for example, are commonly infested with numerous 
fungi of many kinds. Mycetozoa, moulds, and more highly organised 
forms are extremely common. In a damp beech forest of JNew 
Zealand I have cut open rotting logs which have been reduced in the 
interior to a semi-transparent, clear, soft jelly, still showing the gram 
* Trans. Linn. Soc., Lond., vol. vi., part 2, 1894. 
