OR, THE HOME-CULTURE OF FRESH- WATER PLANTS. 



branched character of its stems, and its smooth, 

 pellucid appearance. The Chara Hedwegia and 

 Char a hispida are both very elegant, and their 

 somewhat angular forms would afford an agree- 

 able variety to the other vegetation. Their pre- 

 sence is indicated in the plate of fish. (Plate IV.) 

 Of the fresh-water Alga the most interesting sec- 

 tions are, perhaps, the Quiverworts, or Oscillatoria, 

 the singular movements of which have led to many 

 conjectures and to much discussion among learned 

 naturalists. They have been thought by some to 

 form, in fresh-water, the same link between vegetable 

 and animal life as that of some of the lower order 

 of marine polyps. In short, the subject is so at- 

 tractive, that I make no apology for introducing 

 here the interesting paper on the subject read by 

 Professor Knowles, of Birmingham, at the late meet- 

 ing of the British Association at Cheltenham : 



" ON THE OSCILLATOR!^, BY PROFESSOR KNOWLES, 



"OF QUEEN'S COLLEGE, BIRMINGHAM. 



" The Oscillatorice belong to a group of plants 

 which seem to stand intermediately between the 

 animal and vegetable kingdoms. 



" With regard to the extraordinary movements 

 observable in this interesting family of Algce^ I have 



