246 H. J. WADDlNGTOtt ON MARINE AQUARIA. 



this may be accomplished by rubbing confervas (marine or fresh- 

 water as may be required) in a mortar with a little water and adding 

 it to the vessel containing them. Fed in this way they are much 

 more interesting when viewed microscopically, as the brilliant 

 colour of the fresh Chlorophyll enables the alimentary canal or 

 stomach to be readily defined ; this food must be more natural 

 than the old method of carmine or indigo. 



The time of year at which we are compelled to make our Whit- 

 stable excursion is much against the successful preservation of any 

 objects that may be found, but the methods we ourselves adopt are 

 as little calculated as the season to conduce to their vitality. If 

 the bottles we take were exposed some days previously, full of sea- 

 water with a small piece of confervas, to light and air, the vegetation 

 which would be formed would probably afford sufficient oxygen to 

 keep the contents in vigour for some time. As an instance of the 

 ease with which small quantities of sea-water containing animal 

 life may be preserved, I show you here a small bottle containing 

 about three ounces of sea-water. This has been in the same condi- 

 tion as you see it for many months. It contains a minute Amasba 

 in large quantity, and has in no way deteriorated from the first day 

 the material was put in. I have also with me this evening an 

 ordinary glass tumbler in which vegetation has been allowed to 

 form. This has remained a perfect marine aquarium for many 

 weeks, and contains several small Hydra. 



From the success I have had in keeping Aquaria I am led to 

 the conclusion that many more forms of marine life might be 

 acclimatized in them. One of the greatest obstacles to success in 

 keeping free swimming forms I believe to be the formation of a 

 thin film or coating which is often very persistent on the surface 

 of the water and which I think is most hurtful. Animals which 

 remain permanently below the surface are little affected by it. 

 Syringing breaks this film very readily, but it soon forms again, 

 and not being capable of cure it has to be endured. However, 

 notwithstanding this, the results are so encouraging for the small 

 amount of time bestowed, that I can unhesitatingly recommend 

 the keeping of Marine Aquaria both as a scientific study and a 

 recreation. 



