358 Ari'ENDix. 



I. MEDUS/E, THYSALIA. 



As we have hitherto been in error and doubt 

 respecting many parts of these animals, and as the 

 mode in which they procure food will doubtless 

 interest many persons, I will here give a connected 

 account of them. 



The oval bladder, which forms the body of the 

 animal, and keeps it swimming on the surface of 

 the water, by the air which it contains, may be so 

 contracted on the back by means of muscles, as to 

 form a sort of comb. By the assistance of this 

 comb the medusa catclies the wind, and is driven 

 about on the surface of the water. The long spiral 

 arms, which are furnished on one side, from top to 

 bottom, with kidney-shaped suckers, hang down, 

 unrolled behind, and follow the floating bladder ; 

 as soon as a fish, or any other animal, touches them, 

 it is caught by the suckers, benumbed by the cor- 

 rosive fluid, and brought near to tlie bladder by a 

 spiral contraction of tlie arm, in which a large en- 

 tirely muscular feeler (te7itaculwn') growing to the 

 basis of the arm, but free at the point, seems to co- 

 operate. When the prey is thus brought near the 

 bladder, innumerable tubes, provided with suckers, 

 (real stomachs,) await it, seize it on all sides, and 

 suck in the soft and soluble parts. Thus satiated, 

 these tube-shaped stomachs swell and contract in 

 an extraordinary manner, the contents are seen to 

 shine through, like dark grains ; while quietly di- 



