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 Jan., 1913 year, as the conditions (harvest, seed-time ploughing, etc.) would vary considerably. "(2) That the district from which the birds to be investigated come should be extensive but not too wide. If all were taken from a small area, local conditions would be too prominent; whereas, if birds were obtained from the whole of Great Britain, the varia~ tions in climate (and consequently in dates of seeding and harvest) would prevent a clear idea being obtained of the changes in the food materials that occurred from month to month. "(3) That field notes ought to be taken when the birds were killed, the following facts being mentioned: (a) name and ad- dress of sender, (b) date and t/me of day, (c) exact locality in which the bird was killed, (d) weather, on account of its influ- ence on insect life, (e) special*notes, if the bird was doing any particular injury." A distinct advance in method over previous work can be seen in the attempt to determine the food for the whole year by making col- lections of birds in the same general locality each month of the year. Although birds were collected where found feeding, attention is given the character of the place where the bird was collected, thus emphasizing the availability of certain kinds of food. The food of the starling (Strnus vulgaris) and of the lark (ztlada arvensis) is given in detail. The final verdict as to the economic value of the starling is as follows: "(1) The starling is very beneficial during the late spring, summer and early autumn months, eating many harmful insects although a number of beneficial ones are also de- stroyed. "(2) During the autumn, a.nd to a less ex- tent in the spring, much harm is done by the consumption of seed corn (particularly wheat); many harmful insects, however, are also destroyed during this period. "(3) Owing to the hct of the bird's autumn and spring migrations, the remedies suggest- 'ed are, either (i) to dress the seed corn with something that renders it distasteful to birds; or (if), if suggestion (i) cannot be carried out successfully, to kill off the autumn mi- grants in large numbers." The following conclusion is reached in re- galZd to the lark: "On the whole the lark is beneficial; but, owing to the injuries done at certain times of the year, there is no reason why it should be specially protected, although its wholesale slaughter is to be deprecated." A table showing the results of the stomach examination of various other birds, which were obtained in insufficient number "for an opinion to be expressed as to their utility," is added. A "List of References" gives a hum- ber of the important European publications on the food of birds. In this paper there appear several original ways of tabulating results. One table gives the number of birds collected each month and the exact locality in which they were collect- ed. A second table gives the date, time, place, locality, weather and sex, and tabulates the different kinds of food under the headings in- juries, benefits, and neutral. A third tabula- tion groups seeds, vegetation, etc., insects, etc., and miscellaneous food under these same headings giving the "times occurred" and "number occurred." The material grouped in this way has been mounted on cardboard. To the student, but perhaps to a less extent to the farmer, this method presents vividly the economic aspect of each meal. As a method of preserving the material permanently, it has disadvantages as compared with the "vial" method. A fourth table presents data from the standpoint of the food articles. It gives the percentage of times each article of fo.d has been taken by the birds examined. A de- scription of the food taken each month brings out clearly the change in food-habits from one part of the year to another and so em- phasizes the necessity of a study of the bird's food the year through. Perhaps the greatest criticism that can be offered is that against the use of the numerical method. To say that five out of twenty birds, or 25 per cent, ate carabid beetles hardly gives us a clear knowledge of the relation of this par- ticular diet to the whole food er the bird's relative taste for carabid beetles. The per- centage-by-bulk method used by the U.S. Biological Survey comes nearer showing the relative importance of the food elements. The value of the numerical method as a guide to the actual destruction acomplished, however, is self evident. A combination of both meth- ods doubtless comes nearest the common aim --"interpretation of economic values."--H. C. BRYANT. BIRDS IN RELATION TO A GRASSHOPPER OUT- BREAK IN CALIFORNIA. By HAROLD C. BRY- ANT (Univ. Calif. Publ. Zool., xI, Novembcr 1, 1912, pp. 1-20). In July, 1912, a plague of grasshoppers was reported from the vicinity of Los Banos, Merced County, California. The author visit- ed the locality and spent a week there in studying the possible bearing of the native bird-life upon the insects. The present pa- per is occupied with an account of the ob- served facts, together with some general re- marks upon the relation of birds to insect outbreaks. It was found that at least fourteen species