104 BRITISH BIRDS. [vol. vi. 



Degree of specialization must be a factor in the rate of reaching 

 maturity, apart from mere size ; furthermore, gi'eater longevity 

 may exist as a partial compensation. 



The chapter on " Steering " goes well into the different 

 methods employed and the varying degrees of proficiency 

 found. The same remark applies to " StojDping and Alight- 

 ing." Then our author gives an anatomical chapter — on the 

 whole very adequate to his purpose — in which " The Machinery 

 of Flight " is described. " Varieties of Wing and of Flight " 

 is an interesting chapter, while in " Pace and Last " ^e have 

 some new observations and some old, familiar arguments — 

 in some of these latter we feel, as we have felt before, that much 

 of the evidence is only " circumstantial," and not very satis- 

 factory. " Wind and Flight" is a long chapter, including as 

 it does the problems presented by the phenomenon of soaring. 

 On this point the author's explanations seem to us both clear 

 and convincing. Finally, under the heading of " Some 

 Accessories," a few lines are given to such questions as Diges- 

 tion, Breathing, and Call-notes, in so far as they have a bearing 

 on or a connexion with the subject of Flight. 



Many of the photographs are beautiful, and all the illustra- 

 tions are adequate to their purpose (but it is unfortunate 

 that fig. 27 should be upside do\^Ti). The book is clearly 

 printed and of convenient size — in every way a welcome 

 addition to the ornithologist's library. A.L.T. 



LETTER 



THE STOMACH OF A WATER-RAIL. 



To the Editors of British Birds. 



Sirs, — In reply to Mr. C. B. Ticehurst's suggestion (p. 72), that 

 the small stomach found inside the ordinary stomach of a Water-Rail 

 was " simply the mucous membrane of the stomach or gizzard which 

 had become separated from the muscular coats " — no ; it was not. 

 It was a distinct stomach, which must have been attached by a pedicle ; 

 it was of cup-like formation, entirely separate from the walls of the 

 stomach. Had the microphotograph of a section of the small stomach 

 which I sent been inserted, it would have been seen that all structures 

 found in the walls ot a stomach were present, including muscle. 



Marjory Garnett. 



