Both portraits above were taken by Mrs. Dr. J. Hitchcock of Canton, New York. Presumably she was the wife of a doctor. The card on the left is an example of an early type of CDV with a vignetted photo mounted on thin cardstock with square corners, a double border, and the line "negatives preserved" at the bottom. This type of card dates from around 1863-1865. The card on the right is a later type with the photo mounted on thicker cardstock with rounded coprners and a backmark printed lengthwise. These cards date from 1968-82.
Apparently Mrs. Dr. Hitchcock kept her studio in Canton for a number of years. Judging from the arresting portrait on the right, she was an excellent photographer.