Concerning birds, Darwin remarks: “It has often been said that parrots become so deeply attached to each other that when one dies the other pines for a long time; but Mr. Jenner Weir thinks that with most birds the strength of their affection has been much exaggerated. Nevertheless, when one of a pair in a state of nature has been shot, the survivor has been heard for days afterwards uttering a plaintive call; and Mr. St. John gives various facts proving the attachment of mated birds. Mr. Bennett relates that in China after a drake of the beautiful mandarin Teal had been stolen, the duck remained disconsolate, though sedulously courted by another mandarin drake, who displayed before her all his charms. After an interval of three weeks the stolen drake was recovered, and instantly the pair recognised each other with extreme joy.” “Dr. Buller says (_Birds of New Zealand_) that a male king lory was killed, and the female ‘fretted and moped, refused her food, and died of a broken heart.’” But there are exceptions to this rule of conjugal attachment and fidelity, as is shown in the following quotation, which completes the curious analogy between human and bird love connubial: “Mr. Harrison Weir has himself observed, and has heard from several breeders, that a female pigeon will occasionally take a strong fancy for a particular male, and will desert her own mate for him. Some females, according to another experienced observer, Riedel, are of a profligate disposition, and prefer almost any stranger to their own mate. Some amorous males, called by our English fanciers ‘gay birds,’ are so successful in their gallantries that, as Mr. H. Weir informs me, they must be shut up on account of the mischief which they cause.” So there are Don Juans even among pigeons! _Intermarriages_ or mixed unions also occur among birds. Says Darwin: “It is certain that distinct species of birds occasionally pair in a state of nature and produce hybrids. Many instances could be given: thus Macgillivray relates how a male blackbird and female thrush ‘fell in love with each other,’ and produced offspring. Several years ago eighteen cases had been recorded of the occurrence in Great Britain of hybrids between the black grouse and pheasant.... A male widgeon, living with females of the same species, has been known to pair with a pintail duck. Lloyd describes the remarkable attachment between a shield-drake and a common duck. Many additional instances could be given; and the Rev. E. S. Dixon remarks that ‘those who have kept many different species of geese together, well know what unaccountable attachments they are frequently forming, and that they are quite as likely to pair and rear young with individuals of a race (species) apparently the most alien to themselves, as with their own stock.’”