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Popular Official Guide to The New York Zoological Park, by William T. Hornaday: a Project Gutenberg eBook
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The Project Gutenberg eBook of The Descent of Man and Selection in Relation to Sex, by Charles Darwin
![Popular Official Guide to The New York Zoological Park, by William T. Hornaday: a Project Gutenberg eBook Popular Official Guide to The New York Zoological Park, by William T. Hornaday: a Project Gutenberg eBook](https://www.gutenberg.org/files/53141/53141-h/images/pmg066.jpg)
Popular Official Guide to The New York Zoological Park, by William T. Hornaday: a Project Gutenberg eBook
![Darwin, C. R. 1871. The descent of man, and selection in relation to sex. London: John Murray. Volume. 2. 1st edition. Darwin, C. R. 1871. The descent of man, and selection in relation to sex. London: John Murray. Volume. 2. 1st edition.](http://darwin-online.org.uk/converted/published/1871_Descent_F937/1871_Descent_F937.2_fig25.jpg)