Hints to Beginners with the Microscope. 247 



Possessed, as tlie confervas are thus found to be, of limitless 

 powers of reproduction, it is no longer surprising that they 

 spread through the water in every direction, and at length 

 reach from, the bottom quite to the surface. As the heat of 

 summer increases, the scene changes — the dead cells, emptied 

 of their contents and filled with air rarefied by the heat, become 

 at length buoyant, and the whole mass rises slowly to the sur- 

 face carrying with it, entangled in its meshes, innumerable hosts 

 of microscopic beings, all of which find food and shelter in the 

 recesses of the floating mass, while the water of the pond is left 

 comparatively destitute of living inhabitants. The principle 

 upon which the microscopic contents of the water are thus col- 

 lected together is very similar to that adopted in clarifying 

 liquids by means of the white of an egg ; the albumen in its 

 fluid state is first equally diffused through every part ; it is then 

 coagulated by heat, and mounts to the top bringing all impuri- 

 ties with it, and leaving the liquid below quite clear and 

 pellucid. 



During* almost the whole of the last summer our only fish- 

 ing ground has been the round pond in front of the palace in 

 Kensington Gardens, the surface of which has been covered 

 with a scum composed of these confervoid growths : of this we 

 have at the present moment a small jar before us which, for a 

 whole week, has afforded us an inexhaustible supply of micro- 

 scopic forms, endless in variety and most interesting in their 

 character. We will place a little of it under the microscope 

 merely for the purpose of enumerating the organisms which 

 it may chance to contain : — Desmidece and Diatoms present 

 themselves in rich abundance; a few splendid volvoces roll 

 about in stately leisure; aonium pectorals shows itself in all 

 stages of development. There are at least twenty species of 

 cilated Infusoria ; two or three gorgeous specimens of Acti- 

 nophrys ; several kinds of Eotifers, young Planariae and various 

 Entomostraca of all ages, Hydra fusca, many minute larvaa of 

 insects, and two or three specimens of Nais proooscidea. Such 

 is the microscopic wealth contained in a minute bunch of con- 

 fervas taken up at random. We might have brought dozens 

 of bottles of water from the same pond without obtaining a 

 specimen worthy of examination. 



These remarks are merely intended as hints to guide the 

 beginner in his first researches. All that we wish to insist 

 upon is, that microscopic animals are always more or less 

 associated with aquatic vegetation, upon or in the vicinity of 

 which only they are to be obtained with any degree of cer- 

 tainty. 



