122 Recent Literature. LJan. 



Some of the species most numerously represented are Starling, 107 stom- 

 achs, Rook, 288, and Black-headed Gull, 137. The results are given in 

 numerical form and the identification of items is in most cases very definite. 

 Summaries for the various species note the number of stomachs contain- 

 ing items of various economic groups. 



The preface explains why no percentage system is used in the following 

 passage quoted from Mr. C. F. Archbald: " it would be unwise to attempt 

 to show the proportion in which the components of their food are consumed 

 because individuals of the same species vary much according to opportunity 

 and their own particular fancy. For this reason it would require records 

 extending over several years, and including observations on an enormous 

 number of birds from different localities, to enable us to draw any definite 

 conclusions as to the proportionate amount of good and harm with which 

 each species should be credited." 



This is the theoretical opinion of one who has not given percentage 

 methods a thorough trial. As a matter of fact even a moderate number of 

 stomachs will give results as to proportions of principal items of food that 

 will not materially be changed by doubling or trebling the number of 

 stomachs. Moreover every economic investigation should aim at ulti- 

 mate completeness, and it is just as well to do the earlier work in the style 

 that must eventually be adopted for handling a large mass of data. 



Among the general conclusions are the following: the Starling and the 

 Rook are too numerous; the Herring Gull is spending more time inland and 

 feeds extensively on grain; it and the Common Gull (Larus canus) should 

 be left unprotected until their numbers have greatly decreased; the Black- 

 headed Gull is beneficial. — W. L. M. 



Feilden on Birds of Trinidad and Tobago. 1 — This paper contains 

 notes on 35 species; about 300 are known from these islands. Notes on the 

 food of several species are included, though few of them are very definite. 

 The most interesting annotation refers to the Oil-bird (Steatornis caripensis) . 

 It is as follows: " The food consists of fruit and berries. It is the only 

 fruit-eating night bird. It feeds on the wing, picking off the fruit as it 

 passes the tree. The stones of the fruit are subsequently ejected from the 

 mouth. A species of palm Thrinax argentea growing in the Botanic gardens 

 was visited nightly by these birds to the number of three or four as long as 

 the tree remained in fruit. As the only known colonies of these birds are 

 on the north coast of the island, it is probable that they made the long 

 journey nightly in order to secure food. The Guacharo ... .is of economic 

 value, the young becoming very fat when about a fortnight old. They 

 are then coUected and the fat melted down into a colorless oil which is used 

 for purposes of cooking and illumination" (pp. 31-32). With all the 

 modern methods of producing light, it would seem the Oil-bird might be 

 excused from serving as a substitute. — W. L. M. 



1 Feilden, G. St. Clair, Notes on some birds of Trinidad and Tobago. Bull. 

 Dept. Agr. Trinidad and Tobago, Vol. xiii, Jan. 1914, pp. 25-33. 



