/2 THE AQUA TIC GA RDEN. 



In this opinion we cannot agree. First, we are not 

 aware that lime is at all an adjunct to the growth of 

 microscopic fungi, and the Manchester water is 

 singularly free from it as compared with that of most 

 towns. We believe the fungoid growth to be due to 

 a surplus of nitrogenous matter in solution, caused, 

 perhaps, by the decay of animal substances to which 

 tanks are liable if not properly attended to. Nitrogen 

 is a necessity and stimulant to the growth of fungi of 

 all kinds, and it is evident that the removal of affected 

 fishes to clear running water where nitrogen is absent 

 would counteract the disease. It has long been known 

 to keepers of fresh-water aquaria that the best way to 

 cure fish affected by the white fungus was to remove 

 them to a tub where the water was constantly dripping 

 from the tap. We have referred to this matter at 

 length because it is one that cannot fail to interest 

 aquarium owners. 



A judicious selection and grouping of aquatic vege- 

 tation adds greatly to the beauty of a fresh-water 

 quarium ; and we have hinted how plants requiring 

 deep soil, as well as those requiring little or none, may 

 be accommodated in the same tank, by planting the 

 former in ordinary flower-pots. These may be so 

 arranged along one or other of the sides as to be 

 only just covered with water, and then it will be pos- 

 sible to grow such semi-aquatic plants as the lovely 

 buck-bean (Menyanthes trifoliata), sun-dew (Drosera 

 rotundifolia and anglica), Polygonum ampJiibiiim, the 



