sentences:  At its southeast end, at Selkirk Yard, the Selkirk Subdivision becomes the Castleton Subdivision.Its northwest end is at the east end of the Mohawk Subdivision, and it junctions the Carman Subdivision at Rotterdam and the Hudson Subdivision at Hoffmans.Amtrak's "Empire Service", "Lake Shore Limited", and "Maple Leaf" operate over the Selkirk Subdivision northwest of Hoffmans.