I have not been able to find a verifiable link between Jacobus Davis and Jonathan. Jacobus' oldest son was named John. John and his family accompanied Jacobus and Nancy Davis when they came to Michigan in about 1835. Both John and Jacobus lived in Brighton Township just east of Pleasant Valley road and just west of the west entrance of what is now Kensington metropark. I think the Jonathan you seek was living in Marion Township around 1850. By the way, there is a Beach buried in what used to be called the Beach cemetery, now called the Pleasant Valley cemetery. There is also a Beach buried in the old Kensington cemetery at Grand River and Kensington road. One of these could be Elisha or his parents. The Beach family was one of the early families in Brighton Township. There are Greens buried in Kensington, too. I know a lot of Greens. I went to school with Rollin Green who is now a Green Oak Twp. supervisor. His family has been in Green Oak since it was separated from Washtenaw County in the 1830's. I will check further on Jonathan L. Davis.