VOL. XXIV.] PHILOSOPHICAL TRANSACTIONS. 2^9 



insinuated themselves into the little shells, insomuch that they could not be sepa- 

 rated without breaking some of the parts of the sponges. 



Fig. 4 represents a small shell or scollop, which by tearing it out of the 

 sponge was a little damaged, as is seen between c and b ; at a there grew to it 

 small parts of red coral, and upon c and d there lay many smaller particles of 

 the same; there was also some coral on that side of the shell turned from the 

 sight. Between b and c we also discovered an animalculum, represented like a 

 snake or an eel ; and I have observed the same not only upon this shell but also 

 on several little stones that I have taken out of sponges. 



I had also a small piece of a sea-shell, which we call a horn, upon which, in 

 four several places, there grew little particles of red coral. This small piece of 

 a sea-horn was grown over with a petrified matter, in which there was a great 

 many small holes; and observing several small long animalcula, that were also 

 surrounded with a petrified matter, and whose figures exactly agreed with those 

 little holes, I began to consider whether these animalcula might not have be- 

 longed formerly to those sea-horns or shells. Fig. 5 represents the said particle 

 of the sea-horn, upon which there grew several small particles of coral between 

 G and H. I met likewise with two small pieces of an ossified or bony matter, 

 which were hollow, and upon which likewise there grew a little coral. 



Now, that red coral should grow in the bottom of the sea is impossible to be 

 conceived ; or that the coral matter, which is found on the forementioned shells 

 and stones, can be said to grow there, is what, with submission, we cannot 

 allow of; but it ought rather to be called a coagulation of such kind of matters, 

 and who knows but that all the white and red coral that is found in the sea, is 

 produced by such a coagulation of parts. As for the particles of the said coral, 

 they are not composed of branches, but they lay by and upon one another, like 

 the great sands that were joined to each other; and when viewed through the 

 microscope, one can easily perceive that the parts of which they are composed 

 were firmly united to each other, and that the ground to which they were fixed 

 was more broad than high. 



I took this forementioned scollop and sea- horn, which was overspread with 

 coral, out of a great sponge; but though I examined several other sponges, yet 

 I could meet with no shells that were covered with coral. 



Now, whereas in the growth of all plants we may observe a sprouting out, 

 which in the beginning we call a stem or stalk, from which stalk boughs or 

 branches are produced, by which their parts become larger and more extended; 

 but in the growth of sponges it happens quite otherwise, for they have no 

 stem as far as appears, nor growing thicker and larger; for their beginning and 

 ending is much of the same magnitude, and out of one of their first produc- 



