30 Rey. L. Guilding’s Observations 
down or lost, the species are not easily described. There can be no 
doubt of the necessity of always giving magnified figures and careful de- 
tails of these animals. An uncoloured outline is also desirable, to shew . 
the peculiar carving of the valves. We might add, with advantage, a 
profile of the back, and highly magnified figures of the scales, spines, 
and countless ossicula which beset the inferior adhering surface of the 
zone, which, added to atmospheric pressure, protect them so effectually 
from the violent washing of the surf, and the attacks of their countless 
enemies. The smaller species in particular, without careful line engrav- 
ings (made with the specimens in sight), it will be difficult to distinguish. 
Where it is necessary to avoid expense, one half only of the figure might 
be coloured, while the other might be left to shew the striz and verruce 
with which the valves are commonly adorned. It would be of great ad- 
vantage if outlines of the valves, deprived of their connecting ligament, 
could be also given: the teeth, fissures, and punctures for muscular in- 
sertion vary much in the different species, and should be always noticed. 
Two specimens of each should be sacrificed for this purpose. If left to 
putrefy in water, or if boiled sufficiently, the fleshy parts are easily se- 
parated, and the valves, well cleaned and scraped, may then be gummed 
in their proper order, with a small interval, on card either white or par- 
tially blackened : one of the sets being reversed. With these should be 
preserved a portion of the detached scales or spines, with a thin slice 
from the inferior surface of the zone, that they may be submitted to the 
microscope. 
They seem to feed entirely by night. Though they remain stationary 
during the day, when disturbed they will often creep away with a slow 
and equal pace, often sliding side-ways, and creeping under the rocks 
and stones for concealment. If accidentally reversed, they soon recover 
their position, by violently contorting and undulating the zone; and for 
defence they sometimes (when detached) roll themselves up like the wood- 
lice. Some of the larger kinds, especially of Acanthopleura, are eagerly 
devoured by the lower orders in the West Indies, who have the folly to 
call them beef: the thick fleshy foot is cut away from the living animal, 
and swallowed raw, while the viscera are rejected. We have here a 
large pale Chiton, which is said to be poisonous. 
The zone of the Acanthopleure is often beset with fuci, while the 
