84 PHILOSOPHICAL TRANSACTIONS. [anNO 1757- 



except in the bone, or part that forms the prop of the animal. In the coral it is 

 testaceous, and in the keratophyta it is horny." 



The observations which Mr. T. made on some kinds of polype-beds, led him 

 to think that what are called polypes, in those bodies which are obsen^ed to come 

 out of and return into the cells, are more than the heads of the animal. He had 

 seen some which had a bag, into which passed their food, which he saw them 

 swallow ; and another bag, into which passed the grossest part of that food, after 

 it was digested. This is the case, for instance, of the plumed polypes, which he 

 described at the end of the 3d memoir, in the work published by him on one 

 kind of fresh -water polypes. 



Mons. Donati had observed several very curious facts in the journey which he 

 made into the mountains. He had, in particular, traced out an immense bed of 

 marine bodies. This bed crosses the highest mountains which separate Provence 

 from Piedmont, and loses itself in the plains of Piedmont. He had likewise ob- 

 served a mass of rock, which forms the extremity of a pretty high mountain, the 

 foot of which is washed by the sea. This rock is, at a considerable height, en- 

 tirely pierced by pholades, that species of marine shell-fish so well known, which 

 digs cells in the stones. It hence appears, that this rock was some time covered 

 by the sea. According to Mons. Donati, the sea has insensibly retired from the 

 parts which were washed by it ; and he thinks that there must have been a very 

 considerable space of time between that and the time when this mountain, pierced 

 by pholades, was covered by the waters of the sea. He deduces his opinion from 

 the following fact. There is in this rock, pretty near the surface of the sea, a 

 natural cavern filled with water. In this earth have been found ancient Roman 

 sarcophagi and lamps. Hence it follows that even in the time of the Romans 

 this part of the rock, in which this cavern is situated, was not under water. As 

 there is but a small distance between the cavern and the surface of the water, it 

 follows that the water has sunk but very little since the time of the Romans. If 

 it has sunk in the same proportion since the time when it covered the top of the 

 rock, there is no doubt but that the time when it was entirely covered by the 

 sea, must have been very distant. If the same manner of reasoning be used with 

 respect to the bed of marine bodies mentioned above, which crosses the moun- 

 tains that separate Provence from Piedmont, we shall be obliged to presume, 

 that the time when those mountains were under the waters of the sea, was at a 

 very great distance from the present. Mons. Donati concludes from these facts, 

 and the consequences deduced from them, that the Mediterranean sea is a very 

 ancient, and not a modern one, as Mons. de BufFon imagines. 



Those who explain all the phenomena of marine bodies found out of the sea, 

 by a universal deluge, do not admit the consequences drawn by Mons. Donati 

 from those marine bodies now under consideration. It is plain that most of the 



