Children are usually quick in distinguishing between their parents and his or her twin: but I have two cases to the contrary. Thus, the daughter of a twin says: "Such was the marvellous similarity of their features, voice, manner, etc. that I remember, as a child, being very much puzzled, and I think, had my aunt lived much with us, I should have ended by thinking I had two mothers." The other, a father of twins, remarks: "We were extremely alike, and are so at this moment, so much so that our children up to five and six years old did not know us apart." I have four or five instances of doubt during an engagement of marriage. Thus: "A married first, but both twins met the lady together for the first time, and fell in love with her there and then. A managed to see her home and to gain her affection, though B went sometimes courting in his place, and neither the lady nor her parents could tell which was which." I have also a German letter, written in quaint terms, about twin brothers who married sisters, but could not easily be distinguished by them. In the well-known novel by Mr. Wilkie Collins of "Poor Miss Finch," the blind girl distinguishes the twin she loves by the touch of his hand, which gives her a thrill that the touch of the other brother does not. Philosophers have not, I believe, as yet investigated the conditions of such thrills; but I have a case in which Miss Finch's test would have failed. Two persons, both friends of a certain twin lady, told me that she had frequently remarked to them that "kissing her twin sister was not like kissing her other sisters, but like kissing herself--her own hand, for example." It would be an interesting experiment for twins who were closely alike, to try how far dogs could distinguish between them by scent. I have a few anecdotes of strange mistakes made between twins in adult life. Thus, an officer writes: "On one occasion when I returned from foreign service my father turned to me and said, 'I thought you were in London,' thinking I was my brother--yet he had not seen me for nearly four years--our resemblance was so great." The next and last anecdote I shall give is, perhaps, the most remarkable of those that I have: it was sent me by the brother of the twins, who were in middle life at the time of its occurrence: "A was again coming home from India, on leave; the ship did not arrive for some days after it was due; the twin brother B had come up from his quarters to receive A, and their old mother was very nervous. One morning A rushed in, saying, 'Oh, mother, how are you?' Her answer was, 'No, B, it's a bad joke; you know how anxious I am!' and it was a little time before A could persuade her that he was the real man."