30 Rev. 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 striae and verrucee 

 with which the valves are commonly adorned. It would be of great ad- 

 vantage if oudines 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 slovy 

 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 oi Acanthopleura, are eagerly 

 devoured by the lower orders in the West Indies, who have the folly to 

 call them heef: 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 Acanthopleura is often beset with fad, while the 



