254 EXPERIMENT STATION RECORD. [Vol.40 



ECONOMIC ZOOLOGY— ENTOMOLOGY. 



The criterion of subspecific intergradation in vertebrate zoology, H. C. 

 Obebholseb {Science, n. ser., f f S (1918). .A"". 1238, pp. U15-167). 



Helping to stabilize nomenclature, S. A. IIohwer (Science, n. ser., 48 

 (1918), No. 1227. pp. 18, Ik). 



The control of destructive animals. E. E. Scholl and J. W. Nett.l (Texas 

 Dept. Agr. Bui. HO (1918), pp. 5-19). — The more destructive birds and mam- 

 mals are briefly considered and directions given for tlieir control. 



A revision of the Microtus californicus group of meadow mice, R. Kellogg 

 (Univ. Cal. Pubs. Zoo/.. 21 {1918), A". /. /</<• /-'. fig. I).— This revision is based 

 upon a study of approximately 790 specimens in 114 localities, all hut one being 

 within Che State of California. Eleven forms are recognized, of which six are 

 described as new subspecies. 



A bibliography of 15 titles is appended. 



Our winter birds. — How to know and how to attract them, F. M. Chapman 

 (New York and London: />. Apph ton d Co., 1918, pp. IX +180, pit. 2. figs. 19). — 

 A popular handbook. 



The migration of North American birds. IV— VI. II. C. Qbebholsb (Bird 

 Lore, 20 (1918), Nos. 3, pp. 119 222, pl. 1 : 4- pp. 286-290. pi. 1; 5, pp. 845-349, 



pl. 1, fig. 1). 



Some useful birds found in Minnesota: Their economic relations to the 

 agriculturist, F. L. Wabhbubh (Minn, state Ent. Ore. \8 (1917), pp. 47. pit. 

 8, figs. 25). — This is a popular account Illustrated by color plates of some of the 

 species considered. 



Pheasants and agriculture. Miss A. F. C.-TT. EVEBSHBD (Jour. Apr. Sci. 

 [England], 9 (1918), No. t, pp. 63 91).— The results of an Investigation of the 

 contents of the crops of 311 pheasants are reported, largely in tabular form. 

 In an introduction by 0. Warburton the nature of the food of the pheasant is 

 briefly analyzed month by month, ns far as it is revealed by the crops sent for 

 examination. 



Woodpeckers and cacao, A. II. RlTCHIX R at. (Jour. Jamaica Agr. N<» .. J2 

 {1918), Nos. 2, pp. 65-69; S, pp. 102 t07). This is a report of an investigation 

 of the economic stains of the Jamaica woodpecker (Centurus radiolatua). 



Diagnosis of a new genus of Anatidae from South America, H. C. Obeb- 

 holseb (Jour. Wash, lead (1918), No. 17, pp. 571, 572). 



The subspecies of Larus hyperboreus, H. C. Obxrhoxskb (\uk, 85 (1918), 

 No. J,, pp. 4C,7-)7',). 



Food habits of the mallard ducks of the United States, W. L. McAtee 

 (V. S. Dcpt. Agr. Bui. 720 (l!>is\. pp. 85, pl. 1).— This is a report of technical 

 studies of the food habits >f three mallard ducks, namely, the common mallard 

 (Anas platyrhyncha) , the dusky or black duck (.4. rubripes), and the southern 

 black duck (A. fulvigula). These river ducks rarely dive so as to disappear 

 entirely beneath the water, hut obtain their food in shallows by dipping the 

 head and neck or by submerging all of the body but the tipped-up tail. Thus 

 the food is usually obtained within 12 to 16 in. of the surface. 



In the study of the common mallard, analyses of the contents of 1,578 stomachs 

 collected in 22 States and 2 Canadian Provinces showed 9.47 per cent of the 

 food to be derived from the animal kingdom. 



In the study made of (be black duck, analyses of the contents of Rf>0 stomachs 

 collected from September to February in 19 States and 2 Canadian Provinces 

 showed the total percentage of vegetable food to be 76.91, or about three times 

 as much animal food as that of the mallard. In the study of the southern 



