486 LIFE HISTORY STUDIES OF ANIMALS. 



systems of descriptive zoology, and will often be glad of the help of pro- 

 fessed systematists. The work can not be well done until it is exactly 

 known what animal is being studied. For want of this knowledge, 

 haidly attainable one hundred and fifty years ago, Reaumur sometimes 

 tells us curious things which we can neither verify nor correct; at 

 times we really do not know what animal he had before him. The 

 student of life histories will find a use for physics and chemistry, if 

 he is so lucky as to remember any. Skill in drawing is valuable, 

 perhaps indispensable. 



If by chance I should be addressing any young naturalist who thinks 

 of attending to life histories, 1 would beg him to study his animals alive 

 and under natural conditions. To pop everything into alcohol and 

 make out the names at home is the method of the collectors, but life 

 histories are not studied in this way. It is often indispensable to isolate 

 an animal, and for this purpose a very small habitation is sometimes 

 to be j)referred. The teacup aquarium, for instance, is often better 

 than the tank. But we must also watch an animal's behavior under 

 altogether natural circumstances, and this is one among many reasons 

 for choosing our subject from the animals which are locally common. 

 Let us be slow to enter into controversies. After they have been hotly 

 pursued for some time, it generally turns out that the disputants have 

 been using words in different senses. Discussion is excellent, contro- 

 -versj'^ usually barren. Yet not always; the Darwinian controversy 

 was heated, and nevertheless eminently productive; all turns upon the 

 temper of the men concerned, and the solidity of the question at issue. 

 One more hint to young students. PerhajDS no one ever carried through 

 a serious bit of work without in some stage or other longing to drop it. 

 There comes a time when the first impulse is spent, and difficulties 

 appear which escaped notice at first. Then most men lose hope. That 

 is the time to show that we are a little better than most men. I remem- 

 ber as a young man drawing much comfort from the advice of a col- 

 league, now an eminent chemist, to whom I had explained my difficul- 

 ties and fears. All that he said was, "Keep at it," and I found that 

 nothing more was wanted. 



I greatly believe in the value of association. It is good that two men 

 should look at every doubtful structure and criticise every interpre- 

 tation. It is often good that two talents should enter into partnership, 

 such as a talent for description and a talent for drawing. It is often 

 good that an experienced investigator should choose the subject and 

 direct the course of work, and that he should be helped by a junior, 

 who can work, but can not guide. It seems to me that friendlj^ criti- 

 cism before publication is often a means of preventing avoidable mis- 

 takes. I am sorry that there should be any kind of prejudice against 

 cooperation, or that it should be taken to be a sign of weakness. There 

 are, I believe, very few men who are so strong as not to be the better 

 for help. One diificulty would be removed if known authors were 



