176 



aquatic %itt 



imprison a foreign body in their shells 

 and perish whilst waiting for the discorn 

 fort to pass away. Possibly something 

 like this happens in the case of Cypris 

 finding an entrance, and the crustacean 

 is, by no means, a desirable prisoner. 

 The larger kinds of snails are the chief 

 victims of Cypris — P. Vortex, to some 

 extent, and the smaller snails are able 

 to escape the attentions of Cypris — pos- 

 sibly being so small there is little room 

 for an entrance. When snail breeding 

 all through a summer has been a failure, 

 any snails hatching out at the advent of 

 cold weather, when Cypris has disap- 

 peared until the spring, almost invariably 

 live through the winter. It is quite dis- 

 tressing to witness the efforts made by 

 snails to escape the tiny persecutor, and 

 little snails may often be seen above the 

 water-line in great numbers, trying to 

 place themselves beyond the enemy's 

 reach, whilst the larger snails attach 

 themselves to a flat surface, and do not 

 protrude their bodies beyond the protec- 

 tive limits of the orifice of the shell, and 

 can be observed in this uncomfortable 

 position for long periods. 



To establish new colonies of fresh- 

 water snails, quite a small pond will 

 produce immense numbers. A broad- 

 leaved water-plant is usually chosen on 

 which to affix eggs, and Potamogeton 

 natans is probably one of the best. A 

 few sticklebacks (no other fish) should 

 be introduced for the purpose of getting 

 rid of Cypris. The fishes may take toll 

 of snail fry to some extent, but their 

 services far outweigh other considera- 

 tions. A handful of duckweed should 

 be sown to carpet the surface of the 

 water, and hide the snails from the rav- 

 ages of water birds and other visitants. 

 A pond such as described has been found 

 extremely successful in several instances. 

 — Real at a meeting of the Malacological 

 Society of London. (Courtesy of the 

 Fishing Gazette.) 



Naples Aquarium 



Whoever visits Naples makes a mis- 

 take if he misses the great aquarium, the 

 most complete in the world. Indeed, the 

 world of science contributes to its sup- 

 port. Our Smithsonian Institution makes 

 to it annually a donation of money. Here 

 are to be seen the sea creatures of the 

 Mediterranean, alive and content. In 

 great glass compartments are the many 

 swimming and creeping things that live 

 beneath the surface of that semi-tropic 

 sea. Separated are they from each other, 

 because most of them agree about as do 

 the lion and the lamb. Here we see a 

 tank in which we behold a number of 

 creatures that somewhat resemble a great 

 brown shoe, with two glaring eyes in the 

 heel. From beneath come eight arms 

 that everlastingly stretch out and again 

 contract, like India rubber. They project 

 themselves, now here, now there ; they 

 grasp Avhatever they touch, they seize a 

 bit of food, and then the arm contracts. 

 Into the stomach beneath the eye of the 

 creature it is irresistibly drawn. But 

 while this is occurring the other arms are 

 stretching in and out, are slipping up and 

 down, are searching near and far for 

 anything possible. The creature moves 

 as though it too were a prey of these rub- 

 ber arms which stick by rows of suckers 

 to whatever they touch, and which have 

 the power of grasping a man and draw- 

 ing him down to the ocean's depths, as 

 easily as they do an unfortunate fish 

 This is the octopus, and the Mediter- 

 ranean Sea is filled therewith. 



Next we turn to a tank in which at 

 first glance we see only rough stones and 

 sand, but on closer examination we per- 

 ceive that some of the rough stones are 

 alive. They are fish that have the power 

 of imitating the objects among which 

 they lie, both in color and form. This 

 one is reddish, that one is brown or black 



