Page:1888 Cicero's Tusculan Disputations.djvu/308

 nothing superfluous, nothing that is not necessary for the preservation of life. Besides, nature has also given these beasts appetite and sense; in order that by the one they may be excited to procure sufficient sustenance, and by the other they may distinguish what is noxious from what is salutary. Some animals seek their food walking, some creeping, some flying, and some swimming; some take it with their mouth and teeth; some seize it with their claws, and some with their beaks; some suck, some graze, some bolt it whole, and some chew it. Some are so low that they can with ease take such food as is to be found on the ground; but the taller, as geese, swans, cranes, and camels, are assisted by a length of neck. To the elephant is given a hand, without which, from his unwieldiness of body, he would scarce have any means of attaining food. XLVIII. But to those beasts which live by preying on others, nature has given either strength or swiftness. On some animals she has even bestowed artifice and cunning; as on spiders, some of which weave a sort of net to entrap and destroy whatever falls into it, others sit on the watch unobserved to fall on their prey and devour it. The naker—by the Greeks called Pinna— has a kind of confederacy with the prawn for procuring food. It has two large shells open, into which when the little fishes swim, the naker, having notice given by the bite of the prawn, closes them immediately. Thus, these little animals, though of different kinds, seek their food in common; in which it is matter of wonder whether they associate by any agreement, or are naturally joined together from their beginning. There is some cause to admire also the provision of nature in the case of those aquatic animals which are generated on land, such as crocodiles, river-tortoises, and a certain kind of serpents, which seek the water as soon as they are able to drag themselves along. We frequently put duck-eggs under hens, by which, as by their true mothers, the ducklings are at first hatched and nourished; but when they see the water, they forsake them and run to it, as to