Animals 



SCIENTIFIC SIDE-LIGHTS 



34 



shook Chile, immense flocks of sea-birds flew 

 inland, as if they had been alarmed by the 

 commencement of some suboceanic disturb- 

 ance. Before this last shock it is also 

 related that all the dogs escaped from the 

 city of Talcahuano. MILNE Earthquakes, 

 ch. 18, p. 307. (A., 1899.) 



169. ANIMALS, LIMITED INTELLI- 

 GENCE OF Inability To Learn by Experience 

 Mingled Folly and Wisdom of Serpent. 

 Fabre states (Souvenirs Entomologiques, 

 pp. 168-177) that a sphex an insect be- 

 longing to the same highly endowed order 

 with ants stocks its nest with paralyzed 

 grasshoppers, which are invariably dragged 

 into the burrow by their antennae. When 

 these were cut off close to the head, the 

 sphex seized the palpi; but when these 

 were likewise cut off, the attempt to drag 

 its prey into the burrow was given up in 

 despair. The sphex had not intelligence 

 enough to seize one of the six legs or the 

 ovipositor of the grasshopper, which, as M. 

 Fabre remarks, would have served equally 

 well. So again, if the paralyzed prey with 

 an egg attached to it be taken out of the 

 cell, the sphex, after entering and finding 

 the cell empty, nevertheless closes it up in 

 the usual elaborate manner. Bees will try 

 to escape and go on buzzing for hours on a 

 window, one-half of which has been left 

 open. Even a pike continued during three 

 months to dash and bruise itself against 

 the glass sides of an aquarium, in the vain 

 attempt to seize minnows on the opposite 

 side. A cobra-snake was seen by Mr. Larard 

 to act much more wisely than either the 

 pike or the sphex; it had swallowed a toad 

 lying within a hole, and could not withdraw 

 its head ; the toad was disgorged, and began 

 to crawl away; it was again swallowed 

 and again disgorged; and now the snake 

 had learned by experience, for it seized the 

 toad by one of its legs and drew it out of 

 the hole. The instincts of even the higher 

 animals are often followed in a senseless or 

 purposeless manner: the weaver-bird will 

 perseveringlywind threads through the bars 

 of its cage, as if building a nest ; a squirrel 

 will pat nuts on a wooden floor, as if he 

 had just buried them in the ground; a 

 beaver will cut up logs of wood and drag 

 them about, tho there is no water to 

 dam up; and so in many other cases. 

 DARWIN Formation of Vegetable Mold, ch. 

 2, p. 26. (Hum., 1887.) 



170. ANIMALS MAKE CLEARING 

 AROUND THEIR HOMES A Resource for 

 Pastime and Protection. He [the visca- 

 cha] lives in a small community of twenty 

 or thirty members, in a village of deep- 

 chambered burrows, all with their pit-like 

 entrances closely grouped together; and as 

 the village endures forever, or for an in- 

 definite time, the earth constantly being 

 brought up forms a mound thirty or forty 

 feet in diameter; and this protects the 

 habitation from floods on low or level 



ground. Again, he is not swift of foot, and 

 all rapacious beasts are his enemies; he 

 also loves to feed on tender succulent herbs 

 and grasses, to seek for which he would 

 have to go far afield among the giant grass, 

 where his watchful foes are lying in wait 

 to seize him; he saves himself from this 

 danger by making a clearing all round his 

 abode, on which a smooth turf is formed; 

 and here the animals feed and have their 

 evening pastimes in comparative security: 

 for when an enemy approaches, he is easily 

 seen ; the note of alarm is sounded, and the 

 whole company scuttles away to their ref- 

 uge. HUDSON Naturalist in La Plata, ch. 

 1, p. 10. (C. &H., 1895.) 



171. 



Enemies Cannot 



Approach Unseen Open Space for Play- 

 ground. The strongest instinct of this 

 animal [the viscacha] is to clear the 

 ground thoroughly about its burrows; and 

 it is this destructive habit that makes it 

 necessary for cultivators of the soil to de- 

 stroy all the viscachas in or near their 

 fields. On the uninhabited pampas, where 

 the long grasses grow, I have often admired 

 the viscachera; for it is there the center 

 of a clean space, often of half an acre in 

 extent, on which there is an even, close- 

 shaven turf; this clearing is surrounded 

 by the usual rough growth of herbs and 

 giant grasses. In such situations this habit 

 of clearing the ground is eminently ad- 

 vantageous to them, as it affords them a 

 comparatively safe spot to feed and disport 

 themselves on, and over which they can fly 

 to their burrows without meeting any ob- 

 struction on the slightest alarm. HUDSON 

 Naturalist in La Plata, ch. 20, p. 303. (C. 

 & H., 1895.) 



172. ANIMALS, MARINE, THEIR 

 MODES OF LIFE Now, amongst marine 

 animals we can recognize three principal 

 modes of life. Some animals simply float 

 or drift about with the currents of the sea 

 and are unable to determine for themselves, 

 excepting, perhaps, within very small lim- 

 its, the direction in which they travel. Such 

 are the countless forms of protozoa, the 

 jellyfishes and medusae, numerous pelagic 

 worms and Crustacea, . . . and many 

 other forms well known to those who are in 

 the habit of using the tow-net. HICKSON 

 Fauna of the Deep Sea, ch. 3, p. 52. (A., 

 1894.) 



173. ANIMALS NOT AUTOMATA 



Protozoa Show Voluntary Movement. 

 There is not the slightest confirmation to be 

 found for the assertion that the lower ani- 

 mals, and children in the early days of life, 

 are merely reflex machines, which make 

 certain movements with mechanical cer- 

 tainty as soon as we press the spring. Even 

 such of the protozoa as undoubtedly belong 

 to the animal kingdom give plain evidence 

 of voluntary movement. The chick just out 

 of the shell executes movements which are 

 in great part at least of the nature of vol- 



