118 NUDIBRANCHIATA.—TRITONIADA. 
itself without sustaining any injury, and floated in 
the water. 
“Although these animals are so fragile, so easily 
destroyed on being taken out of their natural 
element, yet they fling themselves about in the 
water without sustaining any injury, without even 
the loss of any of the digitated processes of the 
fins; yet when there is much movement of the 
water, in carrying the glass from one place to 
another, they are evidently disturbed and restless, 
and the fins are dropped. If, therefore, a slight 
motion of the water disturbs them, what can 
become of these delicate Mollusks durmg tempes- 
tuous weather? Can they be similar to the delicate 
ephemera, doomed to live merely for the space of 
a day, and perish in myriads? From the immense 
number seen only from the ship,—and how many 
myriads more extended beyond ourrange of vision !— 
it conveyed to the mind some idea of the profusion 
of living beings inhabiting the wide expanse of 
ocean, and a feeling of astonishment at the incon- 
ceivable variety of forms and constructions to 
which animation has been imparted by creative 
ower. 
“The tail of this animal has been described as 
resembling that of a lizard. The comparison is good, 
not only with regard to form, but also (with, perhaps, 
a little more flexibility) to motion when in action. 
Sometimes the animal throws its tail up to the 
body, as if intended to brush off any annoying 
object, and at other times it has been observed to 
turn the head towards the side, as if for a similar 
purpose ; it seems in the action of eating to resemble 
a caterpillar.” * 
* Proc. Zool. Soc. for 1836. 
