THE AMSTERDAM AQUARIUM. 385 



carefully kept warm, the heat of the water being maintained at 

 between 70° and 80° F. 



Besides the fish, the end hall contained a considerable number 

 of amphibians — Frogs and Newts. Here one saw the Red-bellied 

 Newt (Molge pyrrhogastra) of Central Europe, whose carmine 

 abdomen contrasted brilliantly with the dull black upper parts. 

 There were also several Olms {Proteus anguineus) — that strange 

 blind Eft from the caverns of Carniola, whose pinkish-white 

 body betokens that it lives in perpetual darkness. The Amster- 

 dam Olms had been exposed to the light, and were gradually 

 becoming greyish. The collection also included eight Mexican 

 Salamanders of huge size — the "Axolotl" of naturalists. All 

 these eight individuals were black, white Axolotls being very 

 rare. However, in the next tank there reposed no fewer than 

 eight white Axolotls, lying huddled up together, their long 

 pinky-white bodies suggesting a number of Ferrets in a basket. 

 The pulsation of the blood in the gills of these albinos was easily 

 discernible. Both black and white Axolotls are the tadpole 

 stage of the Amblystoma tigrinum, and there were a couple of 

 magnificent Amblystomce in the Aquarium; their richly mottled 

 skins well merited the name " tigrinum," bestowed on them by 

 scientists. 



Returning by the long hall first entered, the survey of the 

 Aquarium was completed by an examination of the fresh-water 

 fish in the series of tanks facing the marine collection. 



Amongst the fish in the fresh-water series were crowds 

 of Black Bass (Micropterus salmonides), in flourishing condi- 

 tion ; the strange Perch-Pike (Lucioperca sandra), a fine fish 

 whose appearance combines the characters of both Perch and 

 Pike; and a Common Carp (Cyprinus carpio), of enormous 

 dimensions. 



A very interesting exhibit was a tank of young Sturgeons 

 (Acipenser sturio), about three feet long from the tip of the 

 snout to the end of the tail. Above these Royal fish swam a 

 teeming shoal of Rainbow Trout (Salmo irideus). 



Last of all, one may mention the huge Purple-black Sala- 

 mander (Sieboldia maxima), from Japan. This species once 

 made the Amsterdam Zoo famous, for as long ago as 1860 one 

 of these hideous Salamanders was brought safely alive to the 



