FUNCTIONS OF THE CEREBRUM. 205 



animals are often such as to leave us in doubt whether they are the result of a 

 mere instinctive impulse or of an intelligent adaptation of means to ends ; and 

 we are guided in our determination chiefly by the uniformity of these actions 

 in the several individuals of the same species. If we analyze any of our own 

 instinctive actions, we shall perceive the same absence of design on our own 

 parts as that which we attribute to the lower animals. No one would assert 

 that the tendency to sexual intercourse is the result of a knowledge of its con- 

 sequences, and of a voluntary adaptation of means to ends ; or that, if we can 

 imagine a man newly coming into the world, in the full possession of all his 

 powers, he would wait to eat, when hungry, until experience had taught him 

 that the swallowing of food would relieve the uneasy feeling. It has been 

 already shown that, in the infant, the act of sucking may be performed even 

 without a Cerebrum ( 197) ; and for this, and other similar actions, therefore, 

 it is doubtful whether consciousness is a requisite condition. Adult animals, 

 whose Cerebral hemispheres have been removed, will eat food that is put into 

 their mouths, although they will riot go to seek it; and this is the case with 

 many Human idiots. When the functions of the Brain are disturbed, or in 

 partial abeyance, as in fever, we often see a remarkable return to the instinctive 

 propensities in regard to food ; and the Physician frequently derives import- 

 ant guidance, as to the patient's diet and regimen, (particularly as to the 

 administration of wine,) from the inclination or disinclination which he mani- 

 fests. The Intelligence of an animal may be further estimated by its degree 

 of educability that is, the facility with which its natural habits may be 

 changed by the influence of man, and the complication of the mental pro- 

 cesses which it appears to perform under its new circumstances. We all 

 know that Insects the most active of all Inv^rtebrated animals are but little 

 susceptible of such influence. It may be doubted whether there ever was a 

 case in which an Insect of any kind could be taught to recognize any one 

 who had been in the habit of feeding it, or to show any other unequivocal 

 mark of intelligence. Bees and other Insects which display much art in the 

 construction of their habitations, and which execute a variety of most curious 

 contrivances, beautifully adapted to variations in their circumstances, appear 

 to be entirely guided in their operations by instinct; since all Bees act alike, 

 under the same circumstances. We do not find one community or individual 

 clever, and another stupid ; and for a Bee to be destitute of its peculiar ten- 

 dency to build at certain angles, would be as remarkable as a Human being 

 without a tendency to eat.* In Insects, as already stated, we can discover 

 little or nothing that is analogous to the Cerebrum of Vertebrata; and it is 

 manifest that their cephalic ganglia correspond chiefly with the ganglionic 

 enlargements at the upper end of the Medulla Oblongata, which are connected 

 with the organs of special sensation, and which have been stated in the pre- 



* The only manifestation of educability which the Author has ever noticed, during a 

 pretty long familiarity with the habits of Bees, is the acquirement of a power of distin- 

 guishing the entrance of their hive from that of others around. When a swarm is first 

 placed in a new box, and the Bees have gone forth in search of food, they often seem 

 puzzled, on their return, as to which is their own habitation; more especially if there be 

 several hives, with similar entrances, in one bee-house; and it has been proposed to paint 

 these entrances of different colours, in order to enable the Bee to distinguish them more 

 readily. In a short time, however, even without such aid, the Bees are seen to dart from 

 a considerable height in the air, directly down to their proper entrances; showing that 

 they have learned to distinguish these by a memorial power. This the Author has ob- 

 served most remarkably, in a case in which a hive is placed in the drawing-room of a 

 house, the entrance to it being beneath one of the windows; the adjoining houses have 

 windows precisely similar, except in the absence of this small passage; and he has often 

 noticed that, when a new stock has been placed in this hive, the Bees are some days in 

 learning the exact position of their house, considerably annoying the neighbours by flying 

 in at their windows. 

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