THE AMSTERDAM AQUARIUM. 383 



The second tank contained huge Codfish (Gadus morrhua), 

 which swam slowly to and fro ; great Weevers (Trachinus draco) 

 — one of the few really poisonous fishes known — lay in the sand, 

 their striped bodies half buried in the yellow carpeting of the 

 tank ; and Grey Gurnard (Trigla gurnardus), whose marbled 

 sides were beautifully spotted with silver, stalked about on their 

 elongated fin-rays as on so many spidery legs. 



The third tank was filled with glittering Herring (Clupea 

 harengus) ; while a huge shoal of Smelts (Osmerus eperlanus) 

 seemed to make the tank itself quiver as their teeming numbers 

 rippled to and fro, like a piece of streaming seaweed entangled 

 in a strong current. On the sand beneath, in contrast to 

 so much beauty, there scuttled a number of fussy King-Crabs 

 (Limulus polyphemus), their mailed bodies recalling those of 

 Armadillos, whilst their long tails resembled the handles of 

 frying-pans. One unfortunate Crab lay sprawling helplessly 

 on its back, like a turned Turtle, whilst its gill-leaflets pulsated 

 in rhythmical sequence, as one might turn over the pages of 

 a book. 



In the fifth tank were some large Codfish, and also some 

 Sapphirine Gurnard (Trigla hirundo). In spite of their odd 

 shape these Gurnard are very beautiful fish. Their carmine 

 bodies and enormous blue gill-fins besprinkled with spots remind 

 the entomologist of some huge grasshopper or locust, rather than 

 of any denizen of the sea ; moreover, the edges of the gill-fins 

 are dazzling with a superb iridescence, which recalls the sheeny 

 hues of a morpho butterfly. 



Further on in this interesting series was a small Shark 

 (Mustelus vulgaris) — the " Smooth Hound" of British fishermen. 

 The curious gill-slits pulsate with every respiration of the fish, 

 like ventilators regulated by a hidden mechanism — as indeed they 

 really are. A number of Dogfish (Scyllium canicula) also swam 

 to and fro, diligently inspecting everything with an intelligent 

 scrutiny very different from the dull apathetic gaze of Cod and 

 Mullet, Haddock and Ling. 



The most interesting of all the marine tanks, however, was 

 that which contained the Sea-Horses {Hippocampus antiquorum) . 

 There were over forty of these curious little creatures on exhibi- 

 tion. Purplish black, like a dried raisin, or dressed in a livery of 



