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PRESIDENT* S ADDRESS SECTION D. 
South Island of New Zealand, is a very peculiar species whose colour 
and markings form a close imitation of the wet, rotten bark on which 
it was found, and on which it was almost indistinguishable, like a mere 
slimy patch. 
We know now that Land Planarians habitually feed upon living 
prey, such as insects and earthworms, the soft parts of which are 
ingested by means of the protrusible, sucker-like pharynx, the Planarian 
holding its victim in a sticky embrace the while. Probably owing 
to their fondness for earthworms, some species have taken to living 
habitually underground. Such, for example, is Geoplana triangulata , a 
large brown species which I frequently turn out of the soil when digging 
in my garden near Christchurch, and which certainly feeds upon earth- 
worms. The Australian G. sanguinea ( G . alba, &c.) is also sometimes 
found underground ; and so is the allied Tasmanian species, G. typJilops . 
The last-named species is very remarkable, owing to the fact that it has 
entirely lost the numerous eyes characteristic of its congeners, a fact 
which I am inclined to attribute to its having taken to a more or less 
completely underground existence. A similarly blind species, described 
by Diesing under the name of Geobia subterranea , occurs in Brazil, and 
is said to live underground in the holes of an earthworm, upon which 
it preys.* Both these eyeless species are white, aud this is certainly 
a very suggestive fact. Doubtless tbe presence of eyes in other species 
and the rich colouration are both to be associated with an occasional 
exposure to tbe light. 
The development of Land Planarians is a subject about which 
practically nothing is known, and which would probably well repay 
patient investigation, especially if studied in comparison with their 
marine allies. Several eggs, associated with a large quantity of liquid, 
milky yolk, are deposited together in a spherical or ovoid capsule of 
horny consistence* When first laid these capsules are of a reddish- 
brown colour ; but in the course of a few hours the colour changes to 
shiny black. They are found abundantly in spring aud summer in 
cryptozoic haunts ;f and in the case of Geoplana Fletcheri the young 
take about a month to develop up to the time of hatching, when the 
cocoon splits open. The cocoon is large in proportion to the size of the 
worm, and before it is laid causes a great swelling to appear in the 
hinder part of the body. Until recently I have always assumed that 
it passes out through the aperture on the ventral surface ; but 
latterly I have observed in the case of Geoplana triangulata that it 
may pass out through the hack of the animal, a large aperture, 
probably of a temporary nature, being visible after the event. This 
took place in captivity; but it is quite possible that the habit may be 
general. 
Some Land Planarians possess a remarkable power of regenera- 
tion of lost parts, so that when the animal is cut up into lengths each 
piece may grow into a new individual. This fact was observed fifty 
years ago by Darwin in the case of Geoplana tasmaniana and of late 
years the same phenomenon has attracted a good deal of attention in 
the case of Bipalium keibeftse, an introduced species common in many 
* Vide Moseley, Quart. Journ. Micro. Sci., N.S., vol. xvii., j>. 289. 
f Buried in the soil in the case of Geoplana triangulata. 
J Loc. cit. 
