88 THE AQUARIAN NATURALIST. 



Next day, the 19th, at noon, another Medusa, ne- 

 cessarily the highest in the series, was observed to 

 have quitted the group, and another swam at large in 

 the evening ; farther, a third having escaped on the 

 following evening, all these three were free. 



Next day, that is on February 21, after vehement 

 clasping at the summit of the mass, a fourth was 

 liberated, while new struggles to escape appeared in 

 the place it had left, and on the morning of the 22nd, 

 six in all were swimming in the water. A seventh, 

 freed on the 23rd, swam with the rest, and these 

 seven, pursuing their course or suspended in equi- 

 libria, resembled as many minute stars. 



At this juncture there was reason to conjecture 

 that the smooth slice or basis of the colony adhering 

 to the watch-glass was something different from the 

 animals that were successively quitting their position 

 above it, and that it was in reality either an entire 

 Hydra or a portion of one ; nor could any doubt upon 

 the subject possibly remain, when on the 25th of 

 March, being entirely free of the Medusae, its long 

 silky-looking tentacula were seen waving in the water. 

 Further, its nature was subsequently unequivocally 

 demonstrated by the germination of a young Hydra 

 from its body a month later, and in May another de- 

 scendant of one or other of the two had established 

 itself independently. 



From the above observations, then, and from nu- 

 merous others of a similar character, certain facts are 

 established which admit of no dispute. Such are 

 1st, the existence of a vigorous Hydra attached to a 

 solid substance, with long, flowing, silky tentacula; 



