HYDRAS. 159 



the parent, so that the old Hydra is often a grandmoth^ 

 er before she is a mother. The young one is hollow, 

 and communicates with the hollow of the parent. It 

 captures food like the parent, and it is said to be no un- 

 common sight to see the old and the young both seize 

 the same worm. In such cases the strongest wins, un- 

 less the worm breaks in the unfilial struggle, when the 

 parts go into the one common stomach. Very often 

 two young Hydras may be noticed growing from the 

 sides of a single older one, instances of which are shown 

 in Fig. 130. The budded young finally separate from 

 the parent, then leading an independent life, and soon 

 producing young Hydras from their own sides, if they 

 have not already done so. 



The creatures are very hardy. They may endure 

 much harsh treatment, and seem to thrive under it. 

 They have been made the victims of many apparently 

 cruel experiments, but they are probably not very sen- 

 sitive to a feeling of pain. The sensation of hunger, 

 and a touch delicate enough to know when a desirable 

 morsel or an obnoxious object comes in contact with the 

 tentacles, are probably the extent of their feelings. 

 Trembley, a Dutch naturalist who studied the Hydra 

 as long ago as 1739, first called attention to the harsh 

 treatment they would endure and live. In a rather 

 quaint, old-fashioned translation it is said that, "If one 

 of them be cut in two, the fore part, which contains the 

 head and mouth and arms, lengthens itself, creeps, and 

 eats on the same day. The tail part forms a head and 



