VOL. XtVIII.] PHILOSOPHICAL TRANSACTIONS. 49I 



and had tliem put immediately into sea- water: however, by the oysters lying on 

 each other, some of the corallines were kept so moist, as to be perfectly alive 

 and brisk. In order to distinguish them more easily, they plucked them off the 

 oysters, and placed them in white earthen plates, and poured as much sea-water 

 over them as would just cover them. After letting them rest for a little while, 

 to recover themselves, they could easily discover, with a magnifying glass of an 

 inch focus, which were alive, and which not: accordingly, Mr. E. cut off" small 

 pieces of several of the liveliest, and placed them in watch-glasses filled with sea- 

 water ; these, after resting a little while, he placed, one after another, on the 

 stage of the microscope. The unusual sight so amazed his friend (who had his 

 doubts), that he could scarcely believe his own eyes ; for he had hitherto ima- 

 gined, with many others, that these corallines were vegetables, and only the re- 

 ceptacles of animals, as many other plants are, and not the proper cases, skins, 

 or coverings, of their bodies. 



The first coralline* that offered itself to their view, was N° 1, pi. 12, where it 

 is represented, in its natural appearance, climbing on the podded fucus a, with 

 irregular thread-like ramifications, as at b; one of which is exhibited magnified 

 at A, in which is observed a broad dark line in the middle of the transparent stem 

 and branches. This is part of the tender body of the animal, and seems as a 

 support for its several heads and stomachs, with the many hands or claws be- 

 longing to each : for at the top of each of the branches we may observe a polype 

 with 20 tentacula, or claws, which do the office of hands, its mouth being in the 

 centre of them, and its stomach underneath, inclosed in a fine transparent cup. 

 The fine outlines represent the horny skin, or outer coat, that serves this com- 

 pound animal as a defence, in the same manner as the shells of testaceous or 

 crustaceous sea-fish. The skin or covering of the arms, that support the cups, 

 is formed in small rings, which gives the animals the more freedom to move 

 about dextrously in seizing their prey. ""^ 



At letter b is the microscopical representation of a still smaller coralline -j- than 

 the former; the size of it a little reduced is expressed at fig. 2. This creeps up, and 

 twines round other corallines by small vermicular tubes, and sends out its curious 

 slender anus itregularly : these arms, in the microscope, look like rows of the 

 smallest beads of a necklace : to the top of each of these is fixed a cup, for the 

 reception of the polypes, the brim of which is curiously indented. These thej 

 saw alive, and extending themselves about in various directions. 



Fig. N° 3, represents part of another coralline,;}: just as it appeared expanded in 

 a plate of sea-water. It is called, in Ray's Synopsis, ed. 3, corallina ramosa cirris ob- 



* Sertularia geniculata, Linn. f Sertularia volubilis. Linn. Gmel. 



I Sertularia antennina. Linn. 



3 r2 



