SHORES OF THE CLYDE AND FIRTH. 
123 
surmounted by a semicircular ruff, which recede to the 
head proper ; and we notice that the head is furnished with 
a pair of small bead-like eyes, placed considerably apart, 
and near the roots of the horns. These latter appendages, 
though properly enough called horns, are more like the ears 
of the owl in shape, and from particular points of view, the 
head altogether very much resembles that of the antic 
appearance of that member of the feathered tribes. All the 
specimens of these creatures I examined I found the ruff 
surmounting the face to be adorned with what appeared 
to be a row of tender tentacles of a very active nature, but 
THE PALUDINA YIVIPARA. 
on a closer watching of these they are found to be parasites, 
living upon the tender body of the creature, for each in 
turn will be seen to leave his upright position and wriggle 
away to another part, where a hold is made again, and the 
same posture taken up as before. From some cause or 
other, whether permanent or not, these whelks seem to be 
the prey of those worm-like parasites, for from the body of 
one specimen I saw a parasite emerge, as if boring itself 
out, and fall in a helpless condition to the bottom of the 
glass, where it continued to live for a time. 
Like his brother of the shore, the paludina is an egg- 
producer, and these tender and minute things are wonder- 
