APPENDIX. 125 



to this country, and with proper appliances for maintaining 

 the water at an equable temperature of about 70 to 8o° 

 Fah., such as is afforded in a large conservatory, might be 

 permanently acclimatised. Of the species which have so 

 far been temporarily maintained may be mentioned the 

 Climbing Perch (A nab as scandens), remarkable for having its 

 branchial organs so modified and enlarged that it is capable 

 of leaving its native element and moving some distance 

 upon land, it even being asserted to ascend trees in search 

 of insect food. Living examples of this fish were received 

 by the writer some years since from Professor Wood-Mason, 

 of the Calcutta Museum, and preserved examples are on 

 view in the Buckland Museum. The Gourami or Peacock- 

 fish (Osphromenus), and the Paradise-fish (Polyacanthus 

 viridiauratus), two beautifully coloured species, having their 

 ventral fins reduced to little beyond a single long thread- 

 like filament, have on several occasions been introduced into 

 English aquaria, and are both remarkable for their nest- 

 building habits. The males of the former species, like 

 those of the Sticklebacks, are noted for their pugnacity, 

 and in common with other allied species are kept spe- 

 cially by the natives of the Malay peninsula for fighting 

 purposes. The Electric Eel (Gymnotus electricus), a native of 

 Brazil, growing to as great a length as five or six feet, and 

 that even surpasses the Torpedo in its electric properties, has 

 been acclimatised and thriven for some years at both the 

 Brighton and Westminster Aquaria. The organs in 

 which the electric energy is stored up in this fish are, 

 structurally, precisely analogous to those of the Torpedo, but 

 are developed in pairs immediately beneath the skin, one 

 pair along the back of the tail and a second pair along the 

 anal fin. A small member of the Sturgeon family, the 

 Sterlet {Accipenser ruthenus), inhabiting the Russian rivers, 

 rarely exceeding a length of three feet, and highly esteemed 

 for the table, has been brought from Russia and successfully 

 acclimatised in the tanks of the Brighton and Manchester 

 Aquaria. Some of the examples now on view in the first- 

 named institution have been resident there for as long a 



