They appear not to be able to free themselves from this mass of bubbles: every shell I have yet found floating in the Indian Ocean possesses these bubbles in a greater or less degree; they were of a purple colour.

I have seen the common garden snail in England emit a nearly similar consistency: they also emit a blue or purple liquid, which colours anything it touches.
The animals of the barnacles (Pentalasmis) attached to these shells assume their purple colours, while the shell remains nearly pure white.
This afternoon we caught an animal (Glaucus, Illustration 10) I had not before seen.

It seemed to represent the order reptilia in the Mollusca, being sluggish in movement, its eyes distinct, sensitive to the touch, its head much resembling a lizard in appearance, and having a very strong unpleasant smell when taken out of the water.

During the hour I observed it in a bucket it remained sluggishly floating on the top, and occasionally swimming by moving its arms slowly along the surface.

The first three that I saw pass the vessel I imagined to be feathers floating on the water.
Its description is as follows: Length from head to tail, a c 1.8 inches.
Length from head to root of tail, a b 0.85 inches.
Length from head to first arm 0.2 inches.
Length from head to second arm 0.45 inches.
Length from head to third arm 0.7 inches.
1st arm.
From centre of back to end of round part, d e 0.3 inches.
From e to the end of short tentacula, e f 0.3 inches.
Ditto to long ditto, e g 0.75 inches.
Diameter of round part and attached tentacula 0.4 inches.
2nd arm.
From centre of back to end of tentacula.