FEB. 4, 1921 abstracts: ornithology 59 



raphy, geology and water resources of the area, with special reference to the 

 feasibiUty of drilling for an irrigation water supply in land not included 

 within the proposed San Carlos reservoir. The Reservation includes a 

 plateau area in the northern and eastern parts, and a basin area along Gila 

 and San Carlos rivers. Igneous and pre-Ouaternary sedimentary rocks 

 were noted in the mountain areas, and the Quaternary Gila conglomerate 

 in lake beds and river alluvium in the basins. 



In 1914, with inadequate dams, the cost of irrigation was $1.34 an acre. 

 Permanent dams are not recommended. The cost of pumped well water 

 would probably be higher, but would be compensated by increased crops. 

 The shallow-well water in the Gila valley is so highly mineralized that it is of 

 doubtful value for irrigation; that in the San Carlos valley is though better 

 but practical experiments should be made. vSeveral structures favorable 

 for artesian supply are described, and a test well is recommended. 



J. D. Sears. 



NAVIGATION. — The prospective utilizaiion of vessel-to-shore radio-compass 

 hearings in aerial and transoceanic navigation. G. W. Littlehales. 

 Journ. Amer. Soc. Naval Engineers 32: 38-44. PI. 1. February, 1920. 



A method of finding the latitude and longitude in aerial and marine navi- 

 gation from vessel-to-station radio-compass bearings is described, and its 

 mathematical theory is expounded. A plate of the construction employed 

 in the practice of the method is given, together with illustrative applications. 



G. W. L. 



ORNITHOLOGY.— 7/i(? birds of North and Middle America. Robert 

 RiDGWAY. U. S. Nat. Mus. Bull. 50, part S. Pp. xvi, 852, pis. 34. 

 1919. 



The eighth part of ''The Birds of North and Middle America'' is a sys- 

 tematic treatment of the Charadriiformes, with descriptions and S3^nonymy 

 of genera and species as in the previous portions of this work. The present 

 volume contains the following families, all of which are referred to the order 

 Charadriiformes under three suborders: (1) Limicolae with families Jacanidae, 

 Oedicnemidae, Haematopodidae, Arenariidae, Aphrizidae, Charadriidae, 

 Scolopacidae, Phalaropodidae, and Recurvirostridae ; (2) Lari with families 

 Rynchopidae, Sternidae, Laridae, and Stercorariidae ; and (3) Alcae vv'ith 

 the single family Alcidae. Of these families, the Arenariidae and Sternidae 

 are here elevated from subfamily rank on what are considered sufhcient 

 anatomical characters. 



vSeven genera are here revived in the groups treated: three, Endomychura 

 Oberholser, Ciceronia Reichenbach, and Alcella vStone, are raised from sub- 

 generic rank; and the four others, Blasipus Bruch, Chroicocephalus Eyton, 

 Hydrocoloens Kaup, and Mesoscolopax Sharpe, are wholly additional. One 

 new genus, Neoglottis, is instituted, with Scolopax melanoleiica Gmelin as 

 type. Four generic groups recognized by some modern authors are con- 

 sidered not separable: Onychoprion Wagler, Melanosterna Blyth, Limno- 

 cinclus Gould, and Leiicopoliiis Bonaparte. 



In this volume 187 species and subspecies are treated. The guillemot 

 known as Cepphus motzfeldi (Benicken), often commonly supposed to be an 

 individual variation, is here given full specific rank; and the same treatment 

 is accorded Uria ringvia Briinnich. The peculiar sandpiper Pisobia cooperi 

 (Baird) is here treated as a good species. The recent Alaskan record of 



