those functions, from which the assimihition of carbon and the evolution of oxypcn 

 rt'sult ; tliat in fine weather a phiiit, consistinf^ chiefly of leaves and stems, will, if 

 coiifini'tl ill the sniiie portion of air, niirht and day, and duly siiiii)liod with carbonic 

 acid durinj^ the sunshine, go on aihliiKj to thr pnipoillan nf <i.ii/<j<n present, so loiijx 

 as it continues healthy, at least up to a certain point. Considering; the (juautity of 

 oxygen generated by a very small portion of a tree or shrub introduced, he SJiw no 

 reason to doubt th<it the iujhuncr of the rcijctdhle mir/ht serve as <i eomplete compen- 

 sation/or (hat of the animal kinydom. 



Dr. "Ward in 1S37 was "(juite certain that a great number of animals would live 

 and thrive" under the treatment we now see perfected by the Aquarium, in which 

 the animal and vegetable respirations counterbalance each other; the volume of air, 

 with the quantity of vegetable matter required, as compared with the size and rank 

 of the animal, is the problem now solved. The result is, the public exhibition in 

 the Loudon Zoological Gardens of lobsters, fish, shells, corallines, sea-anemones, 

 sponges, and lithophytes, &c., in their natural state, with their brilliant colore and 

 peculiar habits all revealed through the glass which surrounds them. Great care 

 has been found necessaiy in procuring pure sea water, and that the barrel in which 

 it is brought, even to the bung itself, should be free from any vitiating subsUmce. 

 The decay of leaves in a fresh water Aquarium was obviated by introducing a few 

 common pond snails (Limnea), which greedily fed upon the decajdng vegetable mat- 

 ter and slimy mucous growth, so as quickly to restore the whole to a healthy state. 

 Experiments have demonstrated the kind of sea weeds necessary to keep up a regu- 

 lar compensation for many months without change of water, and this scientific toy, 

 if toy it can be called, when its beauty and value, with the possible discovery of 

 new coloring matters, modes of propagation of fish, &.C., are considered, is now quite 

 a fashion. Beautifully has the American poet sung : 



"Look on this beautiful -world, and read the truth 

 In her fair page : see every season brings 

 New change to her of everlasting youth ; 

 Still the green soil with joyous living things 

 Swarms ; the wide air is full of joyous wings ; 

 And myriads still are happy in the sleep 

 Of ocean's azure gulfs, and where he flings 

 The restless surge. Eternal love doth keep 

 In his complacent arms the earth, the air, the deep." 



Bri/ant. 



The Domestic Aquarium is not usually accompanied by a fountain as shown in the 

 wood cut, but is simply a glass water-tight case, filled, as represented, by various 

 marine auimals. It is somewhat amusing, and we have no doubt true, that individ- 

 uality of dispositions has been discovered in the specimens of the same family, even 

 amou"; the smallest. 



