SKA-WRKATHS. 181 



The hydra feeds on the larvae of insects. Though 

 less i'ormidable than its mythologic namesake, its 

 natural properties ar(% to say the least, quite as re- 

 markable. What can be more insignififant to all 

 ap[jeaiance than a creature so small that its thread- 

 like body cannot very well be studied without the 

 aid of a magnifying-glass or a microscope ! But 

 what more curious in reality ! And how greatly 

 has the discoverer been rewarded for his devotion to 

 science by the ever-increasing importance of the 

 facts be has made known! It is thus that Nature 

 rewards the labourers who devote their lives to the 

 contemplation of her marvellous works. 



Hydras proper inhabit the fresh waters ; sea-wreaths 

 or sertulariae, which have an analogous structure, 

 are well known to those observers of nature who 

 pursue their studies on the shores of the ocean. 

 The buds, which in the case of the hydras proper 

 generally detach themselves from the mother-stalk, 

 remain fixed to it in the case of the sertuUiriau 

 polypi. The result is that a horny polypier is foraied 

 exteriorly, not interiorly, the polypi being enclosed 

 in the orifices of the horny envelope. The latter 

 also assumes the most varied forms. It often fixes 

 itself at the bottom of the sea, but also often rests 

 there without rooting itself. The polypier of the 

 hydra proper adheres to the soil by its base. In its 



