BY THE BUDDING PROCESS. 



55 



but at the same time lives in common with others like itself, 

 and forms what is called a compound individual. Between 

 these two kinds there are, however, all possible gradations ; but 

 as it is not germane to my purpose to describe them, I merely 

 mention the fact, for the sake of future reference, and then pass 

 on to what is most pertinent to our subject. 



The strictly independent individual is one in which all the 

 parts of the organization, which belong to animals of this or that 

 particular group, are fully represented in a single body. To com- 

 mence with a most familiar 

 instance, I will draw your 

 attention to the animal 

 which is represented here 

 (fig. 27). It is known by the 

 name of Hydra, and belongs 

 to the same type of animals, 

 namely, the Zoophytes, as 

 the jelly-fishes, corals, star- 

 fishes, &c., but is one of the 

 simplest of them all, in every 

 respect. It is to all intents 

 and purposes a simple elon- 

 gated sac (s), with slender, 

 hollow prolongations (t) ar- 

 ranged around its mouth. 

 These prolongations, which 

 vary in number from five 

 to eight, are called the ten- 

 tacles, and are used as feel- 

 ers, and for the purpose of 

 seizing the food, which is 

 mostly living animals, and Fig. 27. 



conveying it to the mouth. The latter opens at the end of the 



Fig. 27. Hydra fusca. Trembly. 14 diam. The Fresh-water Hydra, with 

 two young (a, c) budding from it. i, the base, attached to a piece of stick ; ., 

 the digestive cavity ; *, tentacles of the adult ; t l , tentacles of the young. Orig- 

 inal. 



