356 The Scottish Naturalist. 



excessive vegetation in the tanks. If the light be in excess r 

 green vegetation is apt to be over abundant, which is very detri- 

 mental to the working of the aquarium, by choking up the pipes, 

 as well as making the tanks look dirty. 



" The relations between . the light, temperature, and air, and 

 those of vegetation, animals, and water," are of the utmost im- 

 portance in the healthy guidance of an aquarium. Great atten- 

 tion has been given to this subject, by Mr. Lloyd, of the Crystal 

 Palace Aquarium and he deservedly has the credit of having 

 perfected a system, which at one time, was a problem to solve ; 

 namely, how to keep marine animals in a state of captivity with- 

 out a direct communication with the sea ? 



Not many years ago, when aquaria were beginning to cause 

 a little sensation on the "continent, a certain noble marquis, now 

 deceased, got Mr. Lloyd up from London to superintend the 

 erection of an aquarium for him in Ayrshire. The mar- 

 quis, who had some ideas of his own with regard to the ar- 

 rangement of the light, temperature, and other general principles 

 which had to be attended to in such an erection, was quite ad- 

 verse to those propounded by Mr. Lloyd 



The aquarium was accordingly put up according to the 

 marquis' directions, and against all Mr. Lloyd's remonstrances ; 

 who, according to the principles already enunciated, concluded 

 that it would not succeed ; and neither it did, for in a very 

 short time the water in the aquarium got into the consistence 

 of pea-soup, and the animals, as a matter of course, all died. 



Mr. Lloyd says, with regard to the Crystal Palace aquarium 

 that, " So carefully balanced are the light, temperature, and air, 

 in relation to the vegetation, animals, and water, that not once 

 during two years (previous to 1873) has any tank had to be 

 cleaned, and the animals thereby disturbed, and there apparently 

 will never be a necessity for any manual cleaning. So perfect 

 an adjustment has never hitherto been attained in any public 

 aquarium for the same period." 



The animals which are accommodated in the Crystal Palace 

 aquarium, and which give a very fair idea of what are contained 

 in such places of popular recreation are: — Sponges; Zoophytes; 

 Sea-ane?nones ; Corals; Jelly-fishes ; Star-fishes and Sea-urchins ; 

 Annelides ; Crustaceans; Barnacles; Shelled and Shell-less Mol- 

 lusca; Cuttle-fishes ; and Fishes. The fishes form by far the 

 largest, and in many respects the most important, interesting, 

 and instructive portion of the collection. 



