THE FRESH-WATER AQrARIUM. 



51 



No. 10. Water-weed. This is one of the most prefer- 

 able of all aquatic plants for an Aquarium. It belongs 

 to ponds and sluggish streams, and grows so easily and is 

 so prolific that, if cut off, and thrown into a tank, it will 

 soon fill up all the space that may be devoted to it. The 

 A. Canadensis has, of course, a northern origin, but is abun- 

 dant in Fishkill Creek, and can be had in the ponds on 

 this island, and particularly in the small streams out the 

 Third Avenue, New York. It is exceedingly ornamental, 

 and of a bright green color. It should be frequently 

 pruned and kept under ; for, unlike most water-plants 

 that require some earth to attach themselves to, the 

 Water-weed, the A, Canadensis or alsinastrum, flour- 

 ishes in a manner wholly independent of its position, 

 and grows as it travels tardily down a stream without 

 being attached to anything but its fellows. In England 

 it acquired notoriety by singular accident. Some of it 

 was sent from Canada to a Cambridge professor, who 

 threw it away. It fell into a drain that emptied into the 

 river, and soon afterwards quite a consternation was cre- 

 ated by the choking up of the river in question by a river- 

 weed. This weed, when examined, proved to be the 

 Anacharis. Since then it has made itself a home in the 

 Thames, where it is called Water Thyme, and is one of 

 the most troublesome of weeds, while in not a few of the 

 English canals it fairly threatens, at times, to lay an em- 

 bargo on navigation. As it is hardy, easily obtained, 

 graceful, gaily colored, prolific, easily thinned out, and ac- 



