It comes from William Simmons's book Spirit of the New England Tribes: Indian History and Folklore (1986) which is a collection of Native American folklore from southern New England. This is one of my favorite folklore books, and every time I look through it something new jumps out at me. Divided into topical chapters like "Shamans and Witches" and "Little People," the book shows how local Native folklore has changed and evolved over the centuries.
The following story comes from the chapter titled "Ghosts and the Devil," so you know it will be creepy. It first appeared in 1936 in The Narragansett Dawn, a publication put out by the Narragansett tribe, with the title "On The Tracks." The author was a man named Lone Wolf.
The land between Westerly and Bradford, Rhode Island is kind of swampy, and is located in the homeland of the Eastern Niantic tribe. Way back in the 19th century a train track was put down through this swampy area, carrying people from Stonington to Providence.
One night a Niantic man was making his way home after being out late. It was very dark, so the man decided to walk along the train track rather than risk losing his way in the swamp. He had his trusty dog with him for companionship and protection. The dog was large and covered in white fur.
No one knows exactly why the man and his dog just didn't hear the train coming, but they didn't. It hit them at full speed and they both died instantly.
Ever since that night their ghosts have haunted the train tracks in that swamp. The Niantic man's ghost has no head, but his dog's ghost is even more frightening. The animal was cut clean in half when the train struck and its ghost walks in two bloody halves down the track, following its headless master. People avoid going into the swamp at night, and have named it White Dog Swamp.
That's the story. Short, sweet, and spooky. William Simmons notes that the current Amtrak route still runs through this area so perhaps passengers should keep their eyes peeled for the ghostly white dog and its master. I don't know if the swamp is still called White Dog Swamp. A search through the US Geographic Survey name locator didn't show anything with that name but perhaps it was not used outside of the Narragansett tribe.
One last thought. I am not of Native American descent and don't have any ownership of this story. I write mostly about Puritan and Yankee folklore, but I think it's important to post local Native American stories occasionally as a reminder that they were and still are an important part of local folklore and history.