[1921 J 
XV. Aves. 
Avcs. 5 
91. — Bonhote, J. L. The nomencla- 
ture of plumage. Ibis. London 1921 
p. 348 ; also H. F. Witherby pp. 567- 
568 and J. L. Bonhote pp. 755-757. 
92. — Bonhote, J. L. Subspecies and 
their part in evolution. Ibis London 
1921 pp. 720-725. 
93. — Booth, H. B. Nesting status 
of the Black-headed Gull in Yorkshire. 
Naturalist London 1921 pp. 159-166. 
94. — Borrer, C. The nestling of the 
Crested Tit. Brit. Bds. London 15 
1921 p. 18. 
95. — Boubier, M. L’oiseaux et son 
milieu, pp. 1-287 Paris (Flammarion) 
1922 8vo. 
96. — Bowles, J. H. Nesting habits 
of the Nighthavvk at Tacoma* Wash. 
Auk Lancaster Pa. 38 1921 pp. 203- 
217. 
97. — Boxberger, L. von. Ornitholo- 
gische Gelegenheitsbeobachtungen aus 
den ostlichen Spanien. Ornith. 
Monatschr. Magdeburg 46 1920 pp. 
65-77 81-91. 
98. — Braess, C. G. Schillings. Ornith. 
Monatschr. Magdeburg 46 1920 pp. 
99-101. 
99. — Brannon, P. A. Notes on Ala- 
bama birds. Auk Lancaster Pa. 38 
1921 pp. 463-464. 
100. — Braun, F. Von der Vogel welt 
der Dt.-Eylauer Parkstrasse. Ornith. 
Monatsb. Berlin 29 1921 pp. 23-29 
40-44. 
101. — Bretscher, K. Zahlenmassiges 
iiber den Vogelzug. Biol. Zentralb. 
Leipzig 41 1921 pp. 558-570. 
102. — Brock, S. E. Bird-associations 
in Scotland. Scot. Nat. Edinburgh 
1921 pp. 11-21 49-58. 
103. — Brooks, A. A twelvemonth 
with the Shorebirds. Condor Berkeley 
Cal. 23 1921 pp. 151-156. 
Bulkley, L. C. vide Williamson. 
104. — Burg, G. v. Misteldrosseln. 
Tierwelt Aarau 31 No. 1 1921 p. 2. 
105. — B[urg], G. v. Weitere Mitteil- 
lungen iiber schweizerische Vogel. 
Weidmann Bulach 1921 No. 6 pp. 6-7. 
106. — [Burg, G. v.\ Der Engadiner 
Ahu. Weidmann Bulach 1921 No. 9 
p. 4. 
107. — [Burg, G. v.] Schweizerische 
Grauspechte. Weidmann Bulach 1921 
No. 10 p. 7. 
108— Burg, G. von. Herkunft der 
Vogel und Saugetiere der Alpen. Weid- 
mann Olten [1912] pp. 1-8. 
109. — Burgess, M. Breeding the 
Blackcap Lory ( Lorius lory). Bird- 
Notes (3) 4 1921 pp. 155-189 photos. 
110. — Burgess, M. L’elovago du 
Lori h calotte noire, Lorius lory (L.). 
L’Oiseau Paris 2 1921 pp. 145-151 
photos. 
111. — Burkitt, J. P. The relation of 
song to the nesting of birds. Irish 
Nat. Dublin 30 1921 pp. 1-10 113-124 ; 
see also Foster, N. H. ibid. pp. 20-21 
and Campbell, D. C. pp. 75-77. 
112. — Burleigh, T. D. Breeding 
birds of War land, Lincoln Co., Mon- 
tana. Auk Lancaster Pa. 38 1921 pp. 
552-565. 
113. — Butler, A. W. Some rare 
Indiana birds. Proc. Indiana Acad. 
Sci. Fort Wayne for 1920 1921 pp. 135- 
139. 
114. — Butterfield, W. R. Notes on 
the local fauna and flora for 1919 and 
1920. Hastings and E. Sussex Nat. 3 
1920 pp. 125-133 156-169. 
115. — Buxton, A. Spring birds 
at Geneva. Trans. Norfolk. Nat. Soc. 
11 1921 (162-167). 
116. — Buxton, P. A. Notes on 
birds from Northern and Western 
Persia. J. Bombay N. H. Soc. 27 1921 
pp. 844-882 map. 
Buxton, P. A. vide Ticehurst. 
117. — Buytendijk, F. J. J. Sens de 
localisation et acquisition d’habitudes 
chez les oiseaux. Arch. Neerl. Physiol. 
Sci. Soc. Holl. Harlem 5 1921 pp. 236- 
243 1 fig. 
118. — Campbell, A. J. The Pallid 
Pardalote (Pardalotus pallidus). Emu 
Melbourne 21 1921 p. 1 pi. i. 
Campbell, D. C. vide Burkitt. 
119. — Cari6, P. Le Merle Cuisinier 
de l’ile Maurice ( Lalage rufiventer 
Sw.) L’Oiseau Paris 2 1921 pp. 2-5 
2 col. pis. 
