The sterile hybrid of Carex diandra Schrank and C. paniculata L. was found in two localities in the north-western part of the province of Overijssel in disturbed peat bog vegetations. The literature referring to this hybrid is reviewed. The name Carex X beckmannii F. W. Schultz was published in 1887, and, if published with a description, has priority over the name C. X germanica Richter ex Aschrs. & Graebn., 1902. The habitats of the hybrid are compared with those of the typical forms of the parents, and of a densely tufted form of Carex diandra which is rather common in the above-mentioned region.