12 



SCIENTIFIC NEWS. 



[Jan. 6, iS 



engraving, measuring from five to six inclies in length, 

 and nearly an inch in diameter. 



The ground colour of the caterpillar is green, with a 

 pale blue band on each ring, and a large blue-black spot 

 is found on each side of the third ring. The most re- 

 markable and attractive features of this caterpillar are its 

 two rows of long, thorny horns or spines on the second 

 and third rings of its body. The horns extend upward, 

 and are gracefully curved backward, being of an orange 

 colour, with black, pointed ends, and similarly coloured 

 minute thorns or projections throughout their length. 

 The smaller black spines are formed on each ring. The 

 great size of this insect and its long thorns give it a 

 wonderfully fine appearance when at rest, but when it is 

 in motion, crawling along the twig of a tree, and shaking 

 its head from side to side, or moving it up or down, 

 it becomes really frightful to behold, although it is per- 

 fectly harmless, and cannot wound or sting with its horns 

 or spines. 



When fully grown, the caterpillar leaves the lofty 

 branches of the tree, and crawls down the trunk to the 

 ground, and there searches for a convenient place to 

 change into a chrysalis. In this restless state it is fre- 

 quently found crawling along a roadway or broad walk. 

 As soon as it finds a convenient location, it goes into 

 the ground to the depth of about six inches, and there 

 builds a sort of nest or abode, having a level bottom and 

 an arched ceiling, both being nicely cemented with a 

 secretion emitted by the caterpillar, so that the nest has 

 walls which are impenetrable to other insects and to 

 moisture. After this grave is built, it strips oif its skin, 

 horns, jaws, and legs, and thus changes into a short, 

 thick chrysalis, having a tolerably hard black shell. In 

 this state it apparently slumbers throughout the winter, 

 till about the middle of June, when it opens its shell, 

 softens the cemented ceiling, and then crawls through 

 the ground to the surface. When it reaches the latter, 

 its wings are closely folded to its body, and are in a 

 moist, soft state, so that it looks more like a grub than a 

 butterfly. In fifteen or twenty minutes, however, the 

 wings are loosened from close contact with the body, 

 and slowly expand until all the veins are extended. 

 They then become tightly stretched and hardened, and 

 the full imago is then ready to rise and fly in the 

 coming night to investigate the flowers and trees in the 

 woods and fields, and to hunt for a congenial companion 

 of its own species. — Scientific American. 



Owls. — Owls hunt by night, and like other birds of 

 prey, return by the mouth the hard indigestible parts of 

 the food in the form of elongated pellets. These are 

 found in considerable quantities about the birds' haunts, 

 and an examination of them reveals the fact that owls 

 prey upon a number of predacious creatures the destruc- 

 tion of which is directly beneficial to man. To show to 

 what extent owls assist in preserving the balance of 

 nature, it may be mentioned that 700 pellets examined 

 yielded the remains of 16 bats, 3 rats, 237 mice, 693 voles, 

 1,590 shrews, and 22 birds. These truly remarkable 

 results were obtained from the common barn owl, and 

 the remains of the 22 birds were those of 19 sparrows, 

 one greenfinch, and two swifts. The tawny and long-eared 

 owls of our woodlands are also mighty hunters, and an 

 examination of their pellets show equally interesting 

 evidence. It must be remembered in this connection 

 that Britain is to a great extent an agricultural country, 

 and that if its fauna is comparatively small, it is not 



the less formidable. We have ten tiny field crea- 

 tures, constituting an army in themselves, and, if not 

 kept under, they would quickly devastate our fields. 

 These ten species include four mice, three voles, and three; 

 shrews. Individually, so tiny are these that any one 

 species could comfortably curl itself up in the divided shell 

 of a horse-chestnut ; but farmers well know that if these 

 things are small they are by no means to be despised. 



The Sense and Senses of Animals. — Sir John Lub- 

 bock, M.P., recently delivered an address on the above 

 subject to the members of the Edinburgh Philosophical 

 Institution. He said that one would gratefully admit 

 that the dog was a loyal and true and affectionate friend, 

 but when we came to consider the nature of the animal 

 our knowledge was very limited. That arose a good 

 deal from the fact that people had tried rather to teach 

 animals than to learn from them. It had occurred to 

 him that some such method as that which was followed 

 in the case of deaf mutes might prove instructive if 

 adapted to the case of dogs. He had tried with a black 

 poodle belonging to himself. He then related several 

 experiments he had made with pieces of card-board 

 with different words marked upon them. He had taken 

 two pieces of card, one blank and the other with the 

 word " food " upon it. He had put the latter on a saucer 

 containing some bread and milk, and the blank card he 

 put on an empty saucer. The dog was not allowed to 

 eat until it brought the proper card to him. This ex- 

 periment was repeated over and over again, and in about 

 ten days the dog began to distinguish the card with the 

 letters on it from the plain card. It took a longer time 

 to make the dog realise the difference between different 

 words. In order to try whether the dog could distin- 

 guish colours, he prepared six cards, marking two oi 

 them blue, two yellow, and two orange. He put one ofr 

 each on the floor and tried to get the dog to bring to him 

 a card with the same colour as one which he showed the 

 dog in his hand. After trying this for three months, he 

 found that his experiment in this direction was a failure. 

 He had always felt a great longing to know how the world 

 appeared to the lower animals. It was still a doubtful point 

 whether ants were able to hear. From experiments 

 which he had made, he had come to the conclusion they 

 had not the power of addressing each other. His im- 

 pression on the whole was that bees and ants were not 

 deaf, but that they heard sounds so shrill as to be be- 

 yond our hearing. There was no doubt about insects 

 seeing. He then went on to relate several experiments 

 he had made with the view of discovering whether dif- 

 ferent insects could distinguish different colours and had 

 any preference for particular colours. The colours of 

 objects must present a very different impression upon 

 insects to that on human beings. The world to them 

 might be full of music which we could not hear, colours 

 which we could not see, and sensations which we could 

 not feel. 



Longevity of Birds. — According to the .£r/,fw«r, many 

 birds, such as the eagle, the swan, and the raven, live 

 more than a hundred years. The parrot, the heron, the 

 goose, and the pelican have been known to live for sixty 

 years ; the peacock for 25 years, the pigeon 20, the crane 

 20, the linnet 25, the goldfinch 15, the lark 13, the 

 blackbird 12, the canary 24, the pheasant 15, the thrush 

 10, the cock 10, the robin redbreast 12, and the wren 

 only 3 years. 



