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Show S4 ~HE PRiNCIPLE OP CnAP. t. . . t ce of an odd inherited move· Another c~riouds I~t~ a~~e wish to obtain an object, will ment associate WI . ' . th ourse of this volume. be ~~v~n In etl~er actions which are commonly per· f 'Ih~e u:~:ro certain circumstances, .in~ep~ndently of hoarbmite and wh I'C 1 to be due to Imitation or some 1 seem . h' o· ' th Thus persons cutting anyt mo sort of sympa Y·. be seen to move their · tl pair of scissors rna Y . WI 1 a. 1 ith the blades of the scissors. jaws simultane?us y w ··t ft twist about their Children lear~Ing to wn e o. e~ idiculous fashion. t ues as their fingers move, In a r voVnhge n a pub l' . uddenly becomes a little hoarse, lC Singer s h been many of those present may be heard, as I ave , . - . f. t of his face, up to his forehead, " raising his ngh~ arn: sl?wly ~~ ~on that the wrist fell heavily on "and th.en droppi_ng It With t J:i;ksodid not occur every night, but " the bndge of his nose. T le t . d cause Some· ,, occasionally and was I· lld epen de n t of any ascer ume . rrh·e gentle· '' times it was' repeated m· cessan t.l y for . an hofut r orb emcamm ee. sore · from the "man's nose was prominent, and Its bridge o en 1 l oi·e was pro· . . 1 At t'me an aw rwarc s " blows which It receivet . one 1 t f the I'ecurrence, night '' ducecl that was I ong m· healin(o)' ' on accoun oH ' ·£ had to removo ,, after ~ight, of the blows which first caused it. 't IS ~I ~ev;re scratch<'S, " the button from the wrist of his night-gown ~s I mace ,, and some means were attempted of tying hl~ . arm. d 1 had never ,, Many years after his death, his son marne.d a l:rJe; l~·ecisely the "heard of the family incident. She, howevm, obs pt bcincr par· ,, same pecuh. an. ty m. her h us b and .' b u t his nose. ' from1 n ob l ,~,s o rrhc " ticularly prominent, has never as yet su ffe I ·ed fromf' t le mop "l e. when " trick does not occur when he I.S h a If- as1 e ep, as ' . or. etx a leep' it is 4 . th t he IS fas as ' dozing in his arm-chau, but e momen . . t. metimcs '4 apt to be0a in. It is, as with his father, In~ermittent d' ~I.ong a part '' ceasin()' for many nirrhts, and some t'n nes a 1m os t mcessan m'th hi·s rirrbt " of eveory night. It i..s..., performed, as 1· t was b Y1 u ·s father ' WI o "1l and . . . h e trick. Sh e per· ''One of his children, a girl, has mhented t e sam 1 . 1 tly modifictl "forms it likewise, W.i th the n.g h t h an d ' b u t in a sh 1o o· l .I·st to drop '' form· fo'r af.t er rai.S l.l lQ' the arm, sh e Cl loes no t a llow t el fW' I l 1 sed hanr " upon ' the ' bridge of thu e nose, but the pa1 m 0 f the h. ad l -c 0 It is also " falls over and down the nose, striking it ra~her ra~I ~: ds of some " very intermittent with this child, not oc~urrmg foi, peno '' months, but sometimes occuning almost mcessantly · CHAP.i. S~RVic:BABLE ASSOCIA'rE:b ltAiHrS. 35 assured by a gentle1nan on who1n I can rely, to clear their throats; but here habit probably con1es into play, a·s we clear our own throats under similar circumstances . I have also been told that at leaping matches, as the perforn1er n1akes his spring, many of the spectators, generally men and boys, move their feet; but here again lJabit probably comes into play, for it is . very doubtful whether women would thus act. Reflex actions.-Reflex actions, in the strict sense of the term, are due to the excitement of a peripheral nerve, which trans1nits its influence to certain nervecells, and these in their turn excite certain muscles or glands into action; and all this 1nay take place without any sensation or consciousness on our part, though often thus acco1npanied. As many reflex actions are highly expressive, the subject must here be noticed at some little length. We shall also see that some of then1 graduate into, and can hardly be distinguished from actions which have arisen through habit. 9 Coughing and sneezing are familiar instances of reflex aqtions. vVith infants the first act of respiration is often a sneeze 1 although this requires the co-ordinated movement of numerous muscles. Respiration is partly voluntary, but mainly reflex, and is performed in the most natural and best manner without the interference of the will. A vast number of con1plex n1ovements are reflex. As good an instance as can be given is tho often-quoted one of a decapitated fi·og, which cannot of course feel, and cannot 11 Prof. Huxley remarks (' Elemcntm·y Pl1ysiology,' 5th edit.. p. 30'5)1 that reflex actions proper to the spinal cord are natu1·al; but, by tho help of the brain, that is through habit, an infinity of a1·tijicial rcilox actions may be acquired. Virchow admits (' Sammlung wi~senschaft. Vortrage,' &c., "Ueber das Riickenmark," 1871, ss. 24, 31) that some reflex actions can hardly be distinguished from instincts; and,. of the latter, it may be aclclctl, some cannot be distingui~hud from m·· Lerited habits. D 2 |