470 



NATURE 



\Oct. 10,1872 



It is in Section V., on" Ideas," that we find some of the 

 most curious observations and suggestive remarks to be 

 met with in the whole work. Animals we know, go 

 mad, and they also vary in their mental capacities, but we 

 do not remember any case of idiocy having been recorded 

 amon'T the lower animals. M. Houzeau, however, tells 

 us he had an idiotic dog, which could not take care of 

 itself, and which behaved in an altogether strange and 

 silly manner. But the most curious thing was that its 

 mother observed its mental incapacity, and acted accord- 

 ingly. From the time when she ceased suckling it, she 

 took great pains to provide its food, bringing it dead birds 

 or pieces of meat, " which she had never done, even for a 

 single day, with any of her other puppies." From this 

 observation, and the well-known fact that animals of the 

 same species differ greatly in their capacity to receive in- 

 struction, our author is convinced that it is only through 

 want of observation that we do not meet with mental 

 derangements of various kinds and degrees among our 

 domesticated animals. The faculties of attention, obser- 

 vation, and imitation, exist in a high degree among most 

 of the higher animals ; and when we add to these a very 

 retentive memory, and a certain amount of direct and 

 voluntary instruction which parents give to their young, 

 much may bo accounted for which has been imputed to 

 those unknown faculties which are termed instinct. Not 

 only does M. Houzeau maintain that the higher animals 

 constantly act by means of intellectual processes alto- 

 gether comparable to our own, but he extends this view to 

 insects. A German naturalist, Gleditsch, relates that he 

 one day spitted a toad on a stick, which he fixed upriijht 

 in the ground. A number of burying beetles {Nccrop/ioni.-; 

 vt'spilld) came around it ; but as they could do nothing with 

 the toad while in the air, they mined under the base of the 

 stick till it fell, and then buried toad and stick together. 

 The circumstances were quite abnormal for the Nccro- 

 pliori, and they acted exactly as an intelligent and reason- 

 ing creature would do. Again, when Pierre Huber placed 

 some humble bees {Bomhiis tcrn-stris) under a glass with 

 a piece of comb so irregular that it would not stand firm 

 on its base, they at once set intelligently to work to make 

 it secure, some holding it up while others built walls and 

 buttresses to make all solid. So, again, when the wasp 

 observed by Erasmus Darwin, which could not carry away 

 a large dead fly because the wind caught the wings, cut 

 them off, and was then able to carry away its prey, it 

 acted exactly as an intelligent and reasoning human being 

 would act. As our author well remarks, whenever such 

 facts are brought forward, the usual cry is — " What an ad- 

 mirable instinct ! " but instead of having recourse to so 

 miraculous a faculty, able to deal with phenomena oc- 

 curring perhaps for the first time in the experience of the 

 race, would it not be more simple to suppose these 

 creatures to possess some small portion of our faculties of 

 observation, of memory, and reflection ? The following 

 remarks on concluding the whole subject of instinct are 

 well worthy of attention. 



"It seems difficult to regard as the effects of a blind 

 instinct such actions as spreading out damp grain in the 

 open air to dry, and taking care of the eggs and the young 

 of captive Aphides. It is difficult to conceive a being 

 perlorming acts so varied and complex, and so bound one 

 to the other in a connected series of labours, without any 



perception of the bond of cause and effect which unites 

 them. Animals perform automatically only simple actions 

 depending on their immediate wants. But when the end 

 requires a large number of preliminary and intermediate 

 operations, of a varied character and dependent one upon 

 the other, can we still suppose the entire line of action to 

 be followed out in ignorance and obscurity ? " And, after 

 stating the fact of the burying beetles, who, after laying 

 their eggs in the bodies of small dead animals, bury them 

 in order that they may not be devoured by birds and 

 beasts of prey, he continues : — ■ 



" If we pretend to see only instinct in this action of the 

 insect, why should we have recourse to a different faculty 

 when man buries his dead ? Has not the act of burying 

 for immediate end, in the one case as in the other, the 

 securing the body from the attacks of carnivorous animals ? 

 Is there not at the same time, in both cases, a more remote 

 end which forms the true motive of the act ? The faculty 

 of invention is doubtless more developed in man than in 

 any species of animal ; it is in him more powerful, more 

 elevated, and often directed by nobler motives. But these 

 differences of quantity and of nobility ought not to blind 

 us to the existence of the faculty in various degrees of 

 development among many animals " (ii. p. 236). Bearing 

 also on this question, we have a curious discussion as to 

 the power of animals to appreciate numbers. It is con- 

 sidered to be established that the magpie can count four, 

 which probably refers to Leroy's experiment with crows 

 (Nature, iii. p. 1S3). The mule is supposed to be able 

 to count as far as five at least, and this is considered to 

 be established by the following observation. There is a 

 short branch line of omnibuses in New Orleans, where 

 each mule makes the journey five times successively 

 before being changed. The veterinary surgeon of these 

 animals called the author's attention to the fact that, 

 whereas at the end of each of the first four journeys they 

 are silent, as they approach the end of the fifth they 

 neigh. But this does not seem satisfactory. The end of 

 the fifth journey may well be determined by the estimation 

 of mere distance, or of time, or by the sense of fatigue, or, 

 what is still more hkely, by some preparations for the 

 change of mules which may be heard or smelt by those 

 arriving. And this is rendered the more probable by an 

 experiment tried by our author himself, showing that dogs 

 cannot count even as far as two. For three successive 

 weeks he repeated the same walk with his dogs on each 

 alternate day ; yet, although the dogs were always eager 

 to go out when their master's preparations were seen, on 

 the last trial, being the tenth repetition, none of them 

 showed any knowledge that the day for an excursion had 

 arrived. But neither is this quite satisfactory, as there is 

 too long an interval between each trial, and it rather in- 

 volves the recollection of a period of time than of a mere 

 number. It can hardly, therefore, be held as proved that 

 the lower animals have any sense of pure number. 



Passing on to the consideration of moral and religious 

 ideas, our author adduces the usual proofs that animals 

 have a sense of right and wrong, but which really show 

 nothing more than that they can be made to acquire cer- 

 tain habits through the fear of punishment or the ex- 

 pectation of reward. We next find the broad statement 

 that the idea of duty is not universal among men, but no 

 evidence is offered, except that no one act is hekl to be a 



