91 
house of the animal than the animal itself: here, however, 
we have been describing the bone and its appendages, 
which are the covering of this animal. Lin nee us described 
it as a bony covering ; and analysis, by that accurate che- 
mist Mr. Hatchett, has shown that Linnaeus was perfectly 
right, seeing that shells are entirely destitute of phosphoric 
acid, and bones have always a portion of it. The bones 
of the mouth of this animal are a curious congeries within 
this* case; the rest of the animal we know very little 
about, and the little there is of it is eaten in some places 
in Scotland and other parts. 
This Echinus was found by some fishermen in the 
islands of Shetland, where it is known by the name of the 
Piper, from the spines being supposed to resemble the 
drones of a bagpipe. The fishermen there say that speci- 
mens are sometimes found with spines nearly a foot jin 
length ; but some allowance must be made for exaggeration 
in all statements of this nature. The figure is nearly the 
size and proportion of the specimen. 
Since writing the above I have seen a small specimen in 
the possession of Mr. Lee, of Hammersmith, about an 
inch and a quarter in diameter, of which the spines are 
some twice that length, but imperfect, and some deeper 
furrowed. Some parts being nearly destitute of spines, 
we find the bone so nearly resembling our species, that 
we consider them the same, as we could not see any 
specific difference. The spines seem to be longer in pro- 
portion in this small specimen than in the larger one. From 
their internal structure we should consider them as adapted 
for growth, and in this they somew hat resemble the struc- 
ture of the stems of some plants, having a kind of central 
pith, apd radiating in divaricating circles from it. We 
* The five teeth are generally elongated inwards, and are composed of 
fine si&y filaments resembling asbe&tus, but are brittle. 
