Economic Series.
No. 1.—The House-Fly as a danger to health. Its Life-history, and how to deal with it. By E. E. Austen. 2 Plates (4 figures), and 3 text-figures. 1913, 8vo. 1d.
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The Guide-Books can be obtained only at the Natural History Museum. Postage extra. Written communications respecting them should be addressed to The Director.