98 PLANARIA. 
issues from the anterior part of the under surface ; and at some distance 
further down is seen the stomach, distributing its numerous ceca to the 
very margin of the body. Finer specimens are speckled red above—paler 
below. Many are of plain, uniform, cream yellow. But the colour de- 
pends greatly on the nature of the food, by which the aspect of the animal 
is entirely changed. Most of those vividly speckled when taken from 
the sea, become quite pale on protracted confinement.—Plate XIV. fig. 1. 
back ; fig. 2, belly. 
It is only on repletion with food of peculiar quality, that the beau- 
tiful interanea can be discovered. Nor is it easy to describe the difficulty 
of representing them accurately, from the size, motion, and opacity of 
the subject. An expert artist, Mr Daniel M‘Culloch, succeeded only 
after the labour of many hours, and the exercise of extraordinary patience. 
Their appearance in an enlarged view is exhibited at fig. 3. Their horns 
may be computed at a sixteenth of the length of the body, perhaps elongat- 
ing more in proportion to the increase of size. It is doubtful whether 
their office is in any respect tentacular, because they are always carried 
upright, or incline a little when the animal is in motion. 
But this is a slugglish inactive creature, unless when stimulated by 
heat or hunger. It is very impatient of any, unless the gentlest, augmen- 
tation of temperature. 
The body is smooth ; it is protected from abrasion by a glutinous 
secretion, which, perhaps, is also instrumental in its agglutination to the 
same spot, should it remain long motionless. 
All the Planarize feed on animal substance, and many eat voraciously. 
The natural habitation of the Horned Planaria is at the depth of 
some fathoms in the sea. In confinement, a shell or stone should be 
provided for its retreat, as it is induced by the smoothness of a glass vessel 
to crawl so far above the surface of the water, that the glutinous matter 
is exhausted, when it becomes incapable of returning, and perishes. 
Also, if the vessel be brimful, it glides over the edge. 
The regenerative properties of the animal are great. Desperate 
wounds and lacerations heal speedily. It survives extraordinary mutila- 
tions, whether accidental or experimental. A specimen having lost the 
