GLAUCUS. Lie 
a query may arise how far they assist the animal in 
floating upon the surface of the water. 
“JT again placed several of the specimens in a 
glass of sea-water; they were full of life, sometimes 
moving about, not very briskly, however, and at 
other times remaining floating upon the surface of 
the water, merely gently moving the fins. As they 
floated upon the surface of the water in the glass, 
the sides of the head, back, tail, fins, &c. exhibited 
at the time a light silvery blue colour, which was 
admirably contrasted with the deeper blue of the 
upper surface, and falling into the elegant pearly or 
silvery white of the under surface of the animal, 
displaying an exceedingly rich and elegant appear- 
ance. Often, when at rest, the animal would drop 
one or more of the fins; but on touching them, they 
would be immediately raised to the former position, 
and that organ was turned back as if to throw off the 
offending object, followed at the same time by a 
general movement of the whole body. On touching 
the animal upon the back, it seemed to display more 
sensitiveness in that than in any other part of the 
body, judging from the effects produced in com- 
parison with similar experiments on other portions 
of the body. For instance, the centre of the back was 
touched lightly and rapidly with a feather, which 
caused the little creature to sink, as if under the 
pressure of the touch, throwing at the same time the 
head, tail, and all the fins upwards, followed by a 
general distortion of the whole body of the animal. 
As if the gentle touch had been productive of severe 
pain, I invariably found every part of the upper 
surface of the body very sensitive when touched, 
displaying a general movement of uneasiness 
throughout the whole of the body of the creature, 
iz 
