VOL. XLVII.] PHILOSOPHICAL TRANSACTIONS. 2^8 



it did not appear possible that they were the constructions of the insects inhabit- 

 ing them. That the only system to be adopted on these matters, was what he 

 mentioned to our author before ; viz. that the bark of these bodies only is a plant 

 properly speaking ; and that this deposits a stony matter, which forms the stalk 

 necessary to sustain it. That then, in his opinion, all the difficulties vanish 

 with regard to the organization of coral. 



In the course of this work our author mentions, that besides the animals to 

 which coral owes its formation, there are 3 kinds, which he describes at large, 

 which pierce and corrode the coral while in the sea, without preventing its in- 

 crease. Contrary to what has been generally received, and to what even Mar- 

 sigli asserts, coral grows among the rocks, and in the caverns of the sea, open 

 to every exposure. It had always been said, that it never grew in caverns open 

 to the north ; they must always be exposed to the south, at least to the east or 

 west ; but on the coast of Barbary, which lies open to the north, coral is not 

 less frequently found than elsewhere. It is generally observed to grow better 

 and more readily in shallow, than in deep water ; and though they generally fish 

 for it at the depth of 10 or 12 fathom, they sometimes get it, though but sel- 

 dom, at 120. 



M. de P. then gives the manner of coral-fishing, and describes 2 different 

 machines made use of for this purpose : one for fishing up the coral where the 

 bottom is smooth ; being the same which is described by Grassendi in his life of 

 Peyreskius. The other, which is called in the Provenqal language the salabre, 

 is constructed so as to be employed where the bottom of the sea is rocky and 

 unequal. He takes notice of the great skill and address of the coral-fishers in 

 the management of these machines, as well as their sagacity in finding, at con- 

 siderable distances from the shore, the very places where some time before they 

 have been successful. He observes that all the productions of the sea, of which 

 he treats, have been considered by naturalists sometimes as stones, and some- 

 times as plants. Their stony substance deceived some, their tree-like appearance 

 others ; insomuch that most writers, who have seen these bodies in their cabi- 

 nets, have only considered their figures. They have denominated pora that class 

 of them which seemed pierced with holes. Of these they found some having 

 their holes large ; and these they called madrepora. There is another confusion 

 among writers concerning these bodies : all those which had a tree-like form, 

 whether their surfaces were smooth, without holes, or whether they were rough 

 and unequal with them, were all styled corals. Those of any other form than 

 that just now mentioned, were called madrepora, lithophyton, or alcyonium. It 

 therefore appears necessary to establish some essential characters, to be able to 

 distinguish these different bodies one from another ; but before these marks of 

 distinction are laid down, our author thinks proper to examine what these bodies 



