9 
as subjects of the vegetable kingdom. They are in general attached 
to other substances by a part, analagous, in its form, to a root ; from 
which proceeds a trunk, ramifying into branches, which, at certain 
times, appear to be beset with flowerets and fruits of beautiful and 
fantastic forms. Their real nature was first ascertained by Peysonell, 
who, in 1727, communicated his observations respecting them to the 
Royal Academy of Sciences at Paris. This accurate observer, not 
only shewed that corals yielded, on the application of heat such 
products as peculiarly belonged to animal substances ; but also pointed 
out several particulars respecting the coral polype, which could not 
fail of determining, that corals belonged entirely to the animal king- 
dom. The observations of Jussieu, Reaumur, Donati, and others, 
confirmed this fact; which, however, was not so generally received, 
but that several learned men still hesitated in admitting that the 
forms which corals bear could be derived from the powers of animal 
life alone. All doubts were, however, removed by the observations of 
Mr. Ellis, in his essay on the Natural History of Corallines, and of 
many curious and uncommon Zoophytes. 
By the experiments of Mr. Hatchett, instituted for the purpose of 
ascertaining the component parts, as well as the mode of formation, of 
different zoophytes, our knowledge respecting these animals has been 
very considerably increased. He was enabled by these experiments 
to ascertain, that corals, and the numerous tribe of zoophytes, with 
which they are connected, differ, in composition, from the varieties of 
bone and shell, only by the nature and quantity of the hardening 
principle, and by the state of the substance with which it is mixed or 
connected. The porcellaneous shells, such as cyprece, &c. were found 
to be composed of animal gluten and carbonate of lime ; and to re- 
semble, in their mode of formation, the enamel of teeth ; the earthy 
matter being blended with the animal gluten. The pearly shells, or those 
composed of nacre or mother of pearl, such as patella, &c. he found 
to be composed of carbonate of lime, and a gelatinous, cartilaginous, 
c 
VOL. II. 
