...But, as Broca has well remarked, the fertility of successive generations of mongrel dogs has never been scrutinised with that care which is thought indispensable when species are crossed... 
Charles Darwin 「The Variation of Animals and Plants Under Domestication, Vol. I.」
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saddler Wartburg utensil
便利！手書き漢字入力検索
この漢字は何でしょう？？