VOL. LVII.] PHILOSOPHICAL TRANSACTIONS. 469 



mouth of the animal, and is capable of great extension : it is amazing to see what 

 large shell fish some of them can swallow, such as muscles, crabs, &c. when it 

 has sucked out the fish, it throws back the shells through the same passage. 

 Through this opening it likewise produces its young ones alive, already furnished 

 with little claws; which, as soon as they fix themselves, they begin to extend in 

 search of food. 



They are found ail round the coasts of England; but the coasts of Sussex 

 and Cornwall furnish us with the greatest varieties of them. The islands in 

 the West-Indies are likewise remarkable for many kinds of them. 



Doctor Gaertner, f. r. s., who has described 4 species of the English ones 

 in the Phil. Trans, says, they have the remarkable property of renewing their 

 claws when they are cut off; and ranks them, perhaps very properly, under the 

 genus Hydra of Linnaeus, or fresh-water polype: which I shall now give a 

 short description of, that we may judge how near this new animal approaches to 

 both of these. 



The hydra or fresh-water polype, is that extraordinary animal so well known 

 to the curious, from the discoveries of Mr. Abraham Trembley, f. r. s., in its 

 re-production after it had been cut into pieces. When it is extended, it is of 

 a worm-shaped figure, and of the same tender substance with the horns of a 

 common snail. It adheres by one end like a sucker to water plants and other 

 substances: the other end, which is the head, is surrounded by many arms or 

 feelers, placed like rays round a centre: this centre is its mouth, and with 

 these arms, which are capable of great extension, it seizes small worms and 

 water insects, and brings them to its mouth, often swallowing bodies larger than 

 itself: when the food is digested in the stomach, it returns the remains of the 

 animals it feeds on, through its mouth again, having no other visible passage 

 from its body. Their manner of multiplying is from eggs, which they produce 

 in autumn; but the most common is from their sides, in which there first 

 appear small knobs, or papillae; as these increase in length, little fibres are 

 seen rising out of the circumference of their heads, which they soon use to 

 procure food. When they are thus arrived at a mature state, they send forth 

 other young ones from their sides: so that though many of them soon fall off, 

 and provide for themselves, yet the anunal frequently branches out into a 

 numerous offspring, growing out of one common parent, each of which not 

 only procures nourishment for itself, but for the whole family. 



I come now to your Lordship's new animal; and, for the satisfaction of the 

 Royal Society, lay before them one of your Lordship's specimens pieserved in 

 spirits, with a dissection of one of them, to show its internal structure, together 

 with three species of actinia, or animal flowers, sent to your Lordship from the 

 new-ceded islands. This compound animal, which is of a tender fleshy 



