950 The American Naturalist. [November, 
by them. The body of the animal, though small, is stuck so full 
of long black needles that it makes a bristiing ball more than 
a foot in diameter. Each spine is a poisoned dart, and as brittle 
as glass. At some points on a reef you can hardly turn a stone 
without encountering this black monster. The Bahaman diver 
and sponge fisherman know them well. I have heard them tell 
of several unfortunate men who received a full dose of this ani- 
mal's poison. As to the pain and cramp which comes from a pm 
prick in the finger administered by this urchin, I can answer by 
frequent experience, and can readily imagine the exquisite torture, 
bordering on madness, which is said to result from closer ac- 
If we leave the reef and wander along the shallows of the bay, 
we see plainly written on its sands evidence of a different though 
by no means scanty population. Here, for instance, I see the 
sand-floor dotted with conical elevations like volcanoes on a 
raised map, with open craters at their tops, or it is there perforated 
with small holes. Resting on many of the latter I see spherical 
masses of a transparent jelly, looking as if it had been thrown out 
by an eruption from below, while long strings of this tremulous 
substance are protruding from others. These are the submarine 
dwellings of annelids — sea worms, which burrow deeply in the 
sand, and lay their tiny eggs, much after the manner of frogs, in 
large masses of jelly, which serve both for food and protection to 
the young. The number of the marine worms is well nigh 
countless. They roll out of nearly every sponge or rock which 
is brought up from the reef Many are painted in the most 
delicate and exquisite colors, and suggest nothing that is repul- 
sive. Some species build elastic tubes, a cluster of which is like 
a bunch of flowers. Each tube, the size of a pencil perhaps 
(when its tenant is undisturbed), is crowned with a circular fringe 
of brown or scarlet feathers. Stoop to pick the flower, and 
presto !— in a wink the worm has drawn in its feathery gills and 
shut the door, which does not open again for some time to come. 
This sand is also dotted with groves and forests of palm-like 
algae, whose slender stems, tufted with green, bear every resem- 
blance to toy trees. 
