The case of the Watseka Wonder is listed by Myers as an incidence of multiple personality strongly suggesting the spiritualist hypothesis. It was originally published in the Religio-Philosophical Journal in 1879 and later in pamphlet form with the title "The Watseka Wonder," by E. W. Stevens. The editor of the journal, highly regarded as a skillful and honest investigator by Myers, spoke highly of Dr. Stevens and claimed to have taken great pains to "obtain full corroboration of the astounding facts" from competent witnesses. The case briefly is the alleged possession of thirteen year old Lurancy Vennum by the spirit of Mary Roff, a neighbor's daughter who had died at the age of eighteen when Lurancy was a child of about fifteen months.

Myers quotes Dr. Stevens, with his abridgements in square brackets:

[Mary Lurancy Vennum, the "Watseka Wonder," was born April 16th, 1864, in Milford township, about seven miles from Watseka, Illinois. The family moved to Iowa in July 1864 (when Lurancy was about three months old), and returned to within eight miles from Watseka in October 1865 (three months after the death of Mary Roff). Lurancy was then about a year and a half old. After two other moves in the neighbourhood, the family moved into Watseka on April 1st, 1871], locating about forty rods from the residence of A. B. Roff. They remained at this place during the summer. The only acquaintance ever had between the two families during the season was simply one brief call of Mrs. Roff, for a few minutes, on Mrs. Vennum, which call was never returned, and a formal speaking acquaintance between the two gentlemen. Since 1871 the Vennum family have lived entirely away from the vicinity of Mr. Roff's, and never nearer than now, on extreme opposite limits of the city.

Rancy," as she is familiarly called, had never been sick, save a light run of measles in 1873.

[On July 11th, 1877, she had a sort of fit, and was unconscious for five hours. Next day the fit recurred, but while lying as if dead she described her sensations to her family, declaring that she could see heaven and the angels, and a little brother and sister and others who had died. The fits or trances, occasionally passing into ecstasy, when she claimed to be in heaven, occurred several times a day up to the end of January 1878; she was generally believed to be insane, and most friends of the family urged that she should be sent to an insane asylum.

At this stage Mr. and Mrs. Asa B. Roff, whose daughter, Mary Roff, as we shall see, had had periods of insanity, persuaded Mr. Vennum to allow him to bring Dr. E. W. Stevens of Janesville, Wisconsin, to investigate the case.]

On the afternoon of January 31st, 1878, the two gentlemen repaired to Mr. Vennum's residence, a little out of the city. Dr. Stevens, an entire stranger to the family, was introduced by Mr. Roff at four o'clock P.M.; no other persons present but the family. The girl sat near the stove, in a common chair, her elbows on her knees, her hands under her chin, feet curled up on the chair, eyes staring, looking every like an "ol` hag." She refuses to be touched, even to shake hands, and was reticent and sullen with all save the doctor, with whom she entered freely into conversation giving her reasons for doing so; she said he was a spiritual doctor, and would understand her.

She described herself first as an old woman named Katrina Hogan, and then as a young man named Willie Canning, and after some insane conversation had another fit, which Dr. Stevens relieved by hypnotizing her. She then became calm, and said that she had been controlled by evil spirits. Dr. Stevens suggested that she should try to have a better control, and encouraged her to try and find one. She then mentioned the names of several deceased persons, saying there was one who wanted to come, named Mary Roff.

Mr. Roff being present, said: "That is my daughter; Mary Roff is my girl. Why, she has been in heaven twelve years. Yes, let her come, we'll be glad to have her come." Mr. Roff assured Lurancy that Mary was good and intelligent, and would help her all she could; stating further that Mary used to be subject to conditions like herself. Lurancy, after due deliberation and counsel with spirits, said that Mary would take the place of the former wild and unreasonable influence. Mr. Roff said to her, "Have your mother bring you to my house, and Mary will be likely to come along, and a mutual benefit may be derived from our former experience with Mary."

On the following morning, Friday, February 1st, Mr. Vennum called at the office of Mr. Roff and informed him that the girl claimed to be Mary Roff, and wanted to go home. He said, "She seems like a child real homesick, wanting to see her pa and ma and her brothers."

Mary Roff was born in Indiana in October 1846. Mary had had fits frequently from the age of six months, which gradually increased in violence. She had also had periods of despondency, in one of which, in July 1864, she cut her arm with a knife until she fainted. Five days of raving mania followed, after which she recognized no one, and seemed to lose all her natural senses, but when blindfolded could read and do everything as if she saw. After a few days she returned to her normal condition, but the fits became still worse, and she died in one of them in July 1865. Her mysterious illness had made her notorious in the neighborhood during her life-time, and her putting his own alleged clairvoyant powers are said to have been carefully investigated "by all the prominent citizens of Watseka, including newspaper editors and clergymen.

It was in February 1878 that her supposed "control" of Lurancy began. The girl then became mild, docile, polite, and timid, knowing none of the family, but constantly pleading to go home," and "only found contentment in going back to heaven, as she said, for short visits."

About a week after she took control of the body, Mrs. A. B. Roff and her daughter, Mrs. Minerva Alter, Mary's sister, hearing of the remarkable change, went to see the girl. As they came in sight, far down the street, Mary, looking out of the window, exclaimed exultantly, "There comes my ma and sister Nervie!" -- the name by which Mary used to call Mrs. Alter in girlhood. As they came into the house she caught them around their necks, wept and cried for joy, and seemed so happy to meet them. From this time on she seemed more homesick than before. At times she seemed almost frantic to go home.

On the 11th day of February, 1878, they sent the girl to Mr. Roff's, where she met her "pa and ma," and each member of the family, with the most gratifying expressions of love and affection, by words and embraces. On being asked how long she would stay, she said, "The angels will let me stay till some time in May;".

The girl now in her new home seemed perfectly happy and content, knowing every person and everything that Mary knew when in her original body, twelve to twenty-five years ago, recognizing and calling by name those who were friends and neighbours of the family from 1852 to 1865, when Mary died, calling attention to scores, yes, hundreds of incidents that transpired during her natural life. During all the period of her sojourn at Mr. Roff's she had no knowledge of, and did not recognize any of Mr. Vennum's family, their friends or neighbours, yet Mr. and Mrs. Vennum and their children visited her and Mr. Roff's people, she being introduced to them as to any strangers. After frequent visits, and hearing them often and favourably spoken of, she learned to love them as acquaintances, and visited them with Mrs. Roff three times.

One day she met an old friend and neighbour of Mr. Roff's, who was a widow when Mary was a girl at home. Some years since the lady married a Mr. Wagoner, with whom she yet lives. But when she met Mrs. Wagoner she clasped her around the neck and said, "0 Mary Lord, you look so very natural, and have changed the least of any one I have seen since I came back." Mrs. Lord was in some way related to the Vennum family, and lived close by them, but Mary could only call her by the name by which she knew her fifteen years ago, and could not seem to realize that she was married. Mrs. Lord lived just across the street from Mr. Roff's for several years, prior and up to within a few months of Mary's death; both being members of the same Methodist church, they were very intimate.

One evening, in the latter part of March, Mr. Roff was sitting in the room waiting for tea, and reading the paper, Mary being out in the yard. He asked Mrs. Roff if she could find a certain velvet head-dress that Mary used to wear the last year before she died. If so, to lay it on the stand and say nothing about it, to see if Mary would recognize it. Mrs. Roff readily found and laid it on the stand. The girl soon came in, and immediately exclaimed as she approached the stand, "Oh, there is my head-dress I wore when my hair was short!" She then asked, "Ma, where is my box of letters? Have you got them yet?" Mrs. Roff replied, "Yes, Mary, I have some of them." She at once got the box with many letters in it. As Mary began to examine them she said, "Oh, ma, here is a collar I tatted! Ma, why did you not show to me my letters and things before?" The collar had been preserved among the relics of the lamented child as one of the beautiful things her fingers had wrought before Lurancy was born, and so Mary continually recognized every little thing and remembered every little incident of her girl-hood....

In conversation with the writer about her former life, she spoke of cutting her arm as hereinbefore stated, and asked if he ever saw where she did it. On receiving a negative answer, she proceeded to slip up her sleeve as if to exhibit the scar, but suddenly arrested the movement, as if by a sudden thought, and quickly said, "Oh, this is not the arm; that one is in the ground," and proceeded to tell where it was buried, and how she saw it done, and who stood around, how they felt, &c., but she did not feel bad. I heard her tell Mr. Roff and the friends present, how she wrote to him a message some years ago through the hand of a medium, giving name, time, and place. Also of rapping and of spelling out a message by another medium, giving time, name, place, &c., &c. which the parents admitted to be all true....

During her stay at Mr. Roff's her physical condition continually improved, being under the care and treatment of her supposed parents and the advice and help of her physician. She was ever obedient to the government and rules of the family, like a careful and wise child, always keeping in the company of some of the family, unless to go in to the nearest neighbours across the street. She was often invited and went with Mrs. Roff to visit the first families of the city, who soon became satisfied that the girl was not crazy, but a fine, well-mannered child.

As the time drew near for the restoration of Lurancy to her parents and home, Mary would sometimes seem to recede into the memory and manner of Lurancy for a little time, yet not enough to lose her identity or permit the manifestation of Lurancy's mind, but enough to show she was impressing her presence upon her own body.

On May 19th, in the presence of Henry Vennum, Lurancy's brother, Mary left control for a time, and "Lurancy took full possession of her own bod recognizing Henry as her brother. The change of control occurred again when Mrs. Vennum came to see her the same day.

On the morning of May 21st Mr. Roff writes as follows: -- 

"Mary is to leave the body of Rancy to-day, about eleven o'clock, so she says. She is bidding neighbours and friends good-bye. Rancy to return home all right to-day. Mary came from her room upstairs, where she was sleeping with Lottie, at ten o'clock last night, lay down by us, hugged and kissed us, and cried because she must bid us good-bye, telling us to give all her pictures, marbles, and cards, and twenty-five cents Mrs. Vennum had given her to Rancy, and had us promise to visit Rancy often."

Mary arranged that her sister, Mrs. Alter, should come to the house to say good-bye to her, and that when Lurancy came at eleven o'clock she should take her to Mr. Roff's office, and he would go to Mr. Vennum's with her. There was some alternation of the control on the way, but the final return of the normal Lurancy Vennum took place before they reached Mr. Roff's office, and on arriving at her own home she recognized all the members of her own family as such, and was perfectly well and happy in her own surroundings. A few days later, on meeting Dr. Stevens, under whose care she had been at Mr. Roff's house, she had to be introduced to him as an entire stranger, and treated him as such. The next day she came to him spontaneously, saying Mary Roff had told her to come and meet him, and had made her feel he had been a very kind friend to her, and she gave him a long message purporting to be from Mary.

In 1890, Richard Hodgson visited Watseka and interviewed many of the principle witnesses of this case. Their testimony was in agreement with Dr. Stevens' presentation. However, Hodgson was unable to get in touch with Lurancy Vennum herself. He draws the following conclusions to the case:

I have no doubt that the incidents occurred substantially as described in the narrative by Dr. Stevens, and in my view the only other interpretation of the case -- besides the spiritistic -- that seems at all plausible is that which has been put forward as the alternative to the spiritistic theory to account for the trance-communications of Mrs. Piper and similar cases, viz., secondary personality with supernormal powers. It would be difficult to disprove this hypothesis in the case of the Watseka Wonder, owing to the comparative meagreness of the record and the probable abundance of "suggestion" in the environment, and any conclusion that we may reach would probably be determined largely by our convictions concerning other cases. My personal opinion is that the "Watseka Wonder" case belongs in the main manifestations to the spiritistic category.