OCR Text |
Show 46 THE PRiNClPtE Oir Two of my horses thus behave when they see or hear the corn g1·v e11 to their neighbours. But. here we ha. ve what may aln1ost be called a tr_ue expre~slon, as pa~vln~ the o-round is universally recognized as a sign of ~age1n~s:s. C~ts cover up their excrements of bo~h kmds ":1th ear tl1 ; an d my oo Tand·f ather 16 saw a . kitten scraping ashes over a spoonful of pure watei: spilt ?n the hearth; so that here an habitual or instinctive act1on was fa~sely excited, not by a previous act or by odour, b~1t by e~esight. It is well known that cats dislike wetti~g. the1r. feet, owing, it is probable, to their having aborJgn1ally Inha~ bited the dry country of Egypt; and when they wet their feet they shake them violently. My daugh~er poured so1ne water into a glass clo~e ~o th: head of a kitten · and it immediately shook 1ts feet 1n the usual manne~ · so that here we have an habitual movement falsely :xcited by an~associated sound instead of by the sense of touch. Kittens, J>Uppies, young pigs and probably 1nany other young animals, alternately push with .their fore-feet against the mammary glands of their n1oth~rs, to excite a freer secretion of n1ilk, or to make It flow. Now it is very common with young cats, and not at all rare with old cats of the con1mon and Persian breeds (believed by son1e naturalists to be specifically distinct), when comfortably lying on a war1n sha-wl or other soft substance, to pound it quietly and alternately with their fore-feet; their toes being spread out ~nd claws slightly protruded, precisely as when. suclnng their mother. That it is the same movement IS clearly shown by their often at the same time takjng a bit of 16 D1· Darwin 'Zoonomia' 1704 vo1. i. p. 100. I Hnd that the fa?t bf cats .p rotrudin' g their fee' t whe'u pleasecl1.s also notw. ed (p. 151) lll this work. CHAP. I. SERVICEABL:tn ASSOCIATElJ 1tABI'fS 47 the shawl into their mouths and sucking it; generally closing their eyes and purring from delight. ~rhis curious movement is comrn.only excited only in association with the sensation of a warm soft surfaee; but I have seen an old cat, when pleased by having its back scratched, pounding the air with its feet in the same manner; so that this action has ahnost become the expression of a pleasurable sensation. Having referred to the act of sucking, I n1ay add that this complex 1novement, as well as the alternate protrusion of the fore-feet, are reflex actions; for they ·are perfonned if a finger moistened with milk is placwl in the mouth of a puppy, the front part of whose brain has been removed. 17 It has recently been stated in France, that the action of sucking is excited solely through the sense of smell, so that if the olfactory nerves of a puppy are .destroyed, it never sucks. In like manner the wonderful power which a chicken possesses only a few hours after being hatched, of picking up sn1all particles of food, seems to be started into action through the sense of hearing; for with chickens hatched by artificial heat, a good observer found that " making a noise with the finger~ nail against "a board, in imitation of the hen-1nother, first taught " thein to peck at their meat." 18 I will give only one other instance of an habitual and purposeless movement. The Sheldrake ( Tad01~na) feeds on the sands left uncovered by the tide, and when a worm-cast is discovered, "it begins patting the. "ground with its feet, dancing as it were, over the ''hole;" and this makes the worm come to the surface. Now Mr. St. John says, that when his tame Sheldrakes 17 Carpenter, 'Principles of Comparative Physiology,' 1854, P· 690; and Muller's' Elements of Physiology,' Eng. translat. vol. ii. P· 936. 18 Mowbray on 'Poultry,' 6th edit, 1830, p. 54. |