c() Part second. 



As has already been mentioned, all animals and plants in the 

 Aquarium come from the Gulf of Naples, and although there are 

 several hundered species in the tanks, yet this is only a small 

 proportion of the number present in the Gulf, which, in its flora 

 and fauna is one of the richest of seas. Now as place could not 

 have been found in the tanks for all the thousands of kinds which 

 these waters harbour, a "selection of the fittest" had to be made, 

 and this choice of the most suitable types was not easy, being 

 conditioned not only by the nature of the animals, but also by the 

 nature of the visitor to the Aquarium. Excluded was naturally 

 the genre ennuyeux, for those not in some way distinguished by 

 colour, form or movement were not worthy to be exhibited to 

 an honourable public. Unsuitable too were all over-large animals 

 such as dolfins, tunny-fish and sharks and, in the same way, the 

 innumerable hosts of those too small. And besides these, such 

 unbridled creatures as the flying-fish which leap over all con- 

 fining boundaries, or mackerel, which at once run their heads 

 against the wall, could not join the well-ordered social conditions 

 of the aquarium tanks. And. whether such beasts as jelly-fish, worms 

 or the horrible Octopus should not have been barred in deference 

 to the aesthetic sense, so well developed in these days, is left to 

 the visitor himself to judge after seing them with his own eyes. 



If, now, in looking at this selected company, one passes over 

 form and colour and observes the movements, then one notices 

 at once that two types are present here in the water which one 

 will not remember having noticed among those animals living on 

 land. These are, firstly the sessile animals, that is, those which 

 are firmly attached to the ground, so that they are unable to 

 move from their positions, and secondly there are those which 

 have no such fixed attachment, but crawl or swim around, their 

 whole life through. True, there are on dry land organisms which 

 are fixed in their surroundings, but as these are well known to be 

 plants, and as the essential distinction between plants and animals 

 is usually held to consist in this, that the latter alone are able 

 to move, the visitor to the aquarium is often inclined to take the 

 sessile animals of the sea for plants. More especially is this the 

 case if, added to that, they look like flowers or like trees, rooted 

 below and branched above. But these sea-anemones, sponges, 

 corals and many others, which are indeed distinguished as "plant- 

 animals" {Zoophytes), are nevertheless all true animals, and the 

 layman will no longer have doubts as to their animal nature 

 when he learns that they swim gaily through the water in their 

 youth, before they settle down to rest and vegetate like plants. 



Between this type of glehae adscripH and those which have 

 no firm foothold at all in life are all the crawling, sliding, walking, 

 clambering, hopping, jumping water-beasts, most of which can, 

 however, swim freely for a shorter or longer time. 



