NOTICES OF NEW BOOKS.
When Prof. Lloyd Morgan publishes a book, we know we shall have a real contribution to the little-known subject of animal psychology. Much, very much, is now published on this phase of evolution, and the study of the habits or behaviour of animals other than man demands two factors—carefully observed facts, and the psychological method. The last is here present in its best form; the first is probably still insufficient for the purpose.
The attitude of the writer of this interesting volume to the position of the two dominant schools of thought on the subject, represented by the Neo-Lamarckians and Neo-Darwinians, is one of caution. To the query, "Are acquired modes of behaviour inherited?" a negative answer "is here provisionally accepted." "Granted that acquired modifications, as such, are not directly inherited, they may none the less afford the conditions under which coincident variations escape elimination"; and we read again, "The acceptance of the conclusion that acquired modes of behaviour are not hereditary, nowise commits us to the belief that heredity has nothing whatever to do with them."
Not only are observational facts required, but the right interpretation of those observations is a matter of no little difficulty, requiring a trained mind and a scientific method. A rapid observation too frequently promotes a hasty conclusion. Prof. Lloyd Morgan gives a good instance of the danger of this mental pitfall. He had been experimenting with a dog and a crooked stick. A man who was passing, and who had paused for a couple of minutes to watch the proceedings, said, "Clever dog that, sir; he knows where the hitch do lie." The remark was the characteristic outcome of two minutes' chance observation, and was