2868 Quadrupeds, fyc. 



his actions, contrasted in a most marked manner with his clumsy gait 

 when on shore ; he plunged, dived, and dashed about in the water in a 

 jovial, rollicking, free-and-easy manner, that showed how perfectly he 

 felt at home. He lays at the bottom like a stone ; he floats on the 

 surface like a cork ; he remains submerged eight minutes at a time. 



No trait in the character of this animal is more interesting than his 

 attachment to his keeper: he follows the Arab wherever he pleases to 

 lead, and is never, seemingly, happy out of his sight: at night the 

 Arab is obliged to sleep so near him as that the creature may touch 

 him ; but as the beast is rather too bulky for a bed-fellow, a girth of 

 seven feet, exceeding even the average admeasurement of an alder- 

 man, the Arab has a sleeping apartment railed off, and, putting a foot 

 through the rails, allows the creature to assure himself, whenever he 

 wakes, that his care-taker is at hand. 



R. 



Observations on the adjustment of the relations between the Animal and Vegetable 

 Kingdoms, by which the vital functions of both are permanently maintained. — This 

 communication will consist of a detail of an experimental investigation, which has 

 been carried on for nearly the last twelve months, and which appears to illustrate, in 

 a marked degree, that beautiful and wonderful provision which we see everywhere 

 displayed throughout the animal and vegetable kingdoms, whereby their continued 

 existence and stability are so admirably sustained, and by which they are made mu- 

 tually to subserve, each for the other's nutriment, and even for its indispensable wants 

 and vital existence. The experiment has reference to the healthy life of fish pre- 

 served in a limited and confined portion of water. It was commenced in May, 1849, 

 and the subjects chosen were two small gold-fish. These were placed in a large glass 

 receiver of about twelve gallons capacity, having a cover of thin muslin stretched 

 over a stout copper wire, bent into a circle, placed over its mouth, so as to exclude, 

 as much as possible, the sooty dust of the London atmosphere, without, at the same 

 time, impeding the free passage of the atmospheric air. This receiver was about half 

 filled with ordinary spring water, and supplied at the bottom with sand and mud, to- 

 gether with loose stones of larger size of limestone tufa, from the neighbourhood of 

 Matlock, and sandstone ; these were arranged so that the fish could get below them, 

 if they wished so to do. At the same time that the fish were placed in this miniature 

 pond, if I may so term it, a small plant of the Vallisneria spiralis was introduced, its 

 roots being inserted in the mud and sand, and covered by one of the loose stones, so 

 as to retain the plant in its position. The Valisneria spiralis is one of those delicate 

 aquatic plants generally selected by the microscopist for the exhibition of the circula- 

 tion of the sap in plants. It throws out an abundance of long, wiry, strap-like leaves, 

 of about a quarter of an inch in breadth, and from one to three feet in length ; these 

 leaves, when the sun shines on them, evolve a continued stream of oxygen gas, which 

 rises in a current of minute bubbles, particularly from any part of the leaf which may 

 have received an injury. 



