|Cziskes, Plat of Harrison Townships 19-20 North, Ranges 18-19 East, p. 60-61.|
Jos is a common abbreviation for Joseph. I know of at least three Joseph Cziskes who were living in Harrison township in Calumet County during this period. The first is Joseph Cziske, born around 1839 in Prussia. One of his sons is also named Joseph Cziske, born around 1870. Both are enumerated in Harrison in the United States federal censuses and Wisconsin censuses from 1870 through 1910. The third possibility is Joseph Cziske, born about 1875. He was the son of Franz Cziske and Justina Malest, who immigrated to Wisconsin from Prussia in 1866, settling in Harrison township.
J. Cziske may be one of the Josephs or it may refer to John Ciske, who was born in Harrison in 1871, but who moved to Menasha in Winnebago County around 1890.
Like most genealogy questions, this requires more research.