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perfectly certain as to the period at which the rutting function commences. 
(6) As animals living in a state of confinement do not exhibit this pheno- 
menon in a very regular or normal manner, they should not be selected for 
experimentation ; and animals which live in a state of freedom should be 
employed. (7) From the mode in which the law ruling the production 
of the sexes has been deduced, it results that this law must be general, 
and apply to all organized beings — that is to say, to plants, animals, and 
man. — Vide Annals of Natural History , January, 1864. 
