32 Transactions. — Miscellaneous. 



may be said to be endowed with mental as well as physical 

 spinnerets. Those oft-repeated acts wdiich are required for 

 the preservation of the animal's life become so interwoven 

 with its mental fabric as to be inseparable from it, and per- 

 formed almost mechanically. Hence, the newly-born animal, 

 inheriting a special bodily structure, and a mental endowment 

 corresponding with it, is apt and ready to perform such 

 acts even without special education. It may be taken for 

 granted that any human being with his bodily organization 

 intact would in process of time learn to walk of his own 

 accord, even if placed in circumstances which had precluded 

 him from seeing any other human creature walk, or from 

 receiving any instruction in the art of walking. 



If we eliminate all such habits as may have been acquired 

 without teaching or observation, we shall find left com_para- 

 tively few lixed habits of animals w^hich, in the present state 

 of our knowledge, cannot be accounted for by the individual 

 having received instruction from its fellows or gained know- 

 ledge from its own observation ; and it is to such habits that 

 I propose to restrict the term "instinct." For the purposes 

 of this paper I will call them " true instincts." These in- 

 stincts are confined almost exclusively to insects. By way of 

 illustration I will take the case of the caterpillar of a butterfly 

 (Thekla) referred to in Darwin's " Posthumous Essay on In- 

 stinct," printed as an appendix to Eomanes' " Mental Evolu- 

 tion in Animals." This caterpillar feeds within the pome- 

 granate ; but when full-fed gnaws its way out (thus making 

 the exit of the butterfly possible before its wings are fully 

 expanded), and then proceeds to attach with silk threads the 

 point of the fruit to the branch of the tree, so that it may 

 not fall before the metamorphosis of the insect is complete. 

 Hence, the larva works on this occasion for the safety of the 

 pupa and of the mature insect wdiich it will never see ; and 

 there is apparently no means by which it can receive instruc- 

 tion, since no visible intercourse takes place between the 

 butterfly which laid the eggs from which the caterpillar is 

 produced and the caterpillar. When considering this pro- 

 blem we must firmly grasp the fact that, although the cater- 

 pillar, the pupa, and the mature insect — the butterfly — are, 

 to outward seeming, three distinct animals, in reality they 

 are but varying phases of the same animal ; just as the infant, 

 the boy, and the man are one and the same human being, but 

 in different stages of existence. The difference in the outward 

 aspect of the insect in the several phases of its existence is 

 indeed the more striking, but the essential facts of the phe- 

 nomenon are the same. The caterpillar, the pupa, and the 

 imago form the various stages of the insect's hfe-cycle, just 

 as the progress from early infancy to old age forms the life- 



