July, ?9o5 THE FUTURE PROBLEMS AND AIMS OF ORNITHOLOGY 95 PARENT FEEDING YOUNG BUSH-TITS The Future Problems and Aims of 0rnithology a A LETTER FROM MR. ?VILLIAM BREXVSTER Cambridge, Mass., Feb. x9, i9o 5. D?,AR MR. i?ISHER: Your questions are so comprehensive and far reaching that I cannot answer all of them without giving more time and thought to the matter than are at pres- ent at my disposal. I will say briefly, however: (i) That of the more general problems in ornithology not related to any one country, that concerning the inter- relation of bird with other animal life--and with plant life--seems to me to be best worth the attention of young ornithologists. By this I mean to say that what is called the "balance of nature" should be more closely studied. The subject is at pres- ent veiled in obscurity. We know for example that herons, kingfishers and loons eat fish; but just what fish do they eat, and upon what do these fish subsist? If on other animal life, what do these other animals eat? Do not the kingfishers and herons eat creatures other than fish? etc. The study of bird migration is another general problem that is not likely to be exhausted for many years to come. (2.) With reference to North American birds it is especially desirable to know more definitely where certain of them do or do not go to spend the winter. The summer distribution of many of them is also but imperfectly known. An especial aA continuation of the series of letters begun in the last issue of Tr?E CONDOR. Mr. Brewstel' has taken up sev- eral specific questions. The answers sufficiently indicate the nature of the questions.--ED.
