260 ALTERNATE GENERATIONS. 



Hydras ; but, beside these, there are certain mem" 

 bers of the community who act as swimmers, to 

 carry it along through the water, others that 

 are its purveyors, catching the prey, by which, 

 however, they profit only indirectly, for others 

 are appointed to eat it, and these feeders may 

 be seen sometimes actually gorged with the food 

 they have devoured, and which is then distrib- 

 uted throughout the community by the process 

 of digestion and circulation. 



It would be hopeless, even were it desirable, 

 to attempt within the limits of such an article 

 as this to give the faintest idea of the number 

 and variety of these Hydroids ; and I will there- 

 fore say nothing of the endless host of Tubula- 

 rians, Campanularians, Sertularians, etc. They 

 are very abundant along our coast, and will well 

 reward any one who cares to study their habits 

 and their singular modes of growth. For their 

 beauty, simply, it is worth while to examine 

 them. Some are deep red, others rosy, others 

 purplt), others white with a glitter upon them, 

 as if frosted with silver. Their homes are very 

 various. Some like the fresh, deep sea-water, 

 while they avoid the dash and tumult of the 

 waves ; and they establish themselves in the de- 

 pressions on some low ledge of rocks running 

 far out from the shore, and yet left bare for 

 an hour or two, when the tide is out. In such 



