Peromyscus maniculatus is a rodent native to North America.
  The deer mouse is small in size, only about 8 to 10 cm long,
  not counting the length of the tail.
Originally,
  the columns of this data frame
  represent the sex (m or f),
  the ages (y: young, sa: semi-adult, a: adult),
  the weights in grams, and the
  capture histories of 38 individuals over 6 trapping
  occasions (1: captured, 0: not captured).
The data set was collected by V. Reid and distributed
  with the CAPTURE program of Otis et al. (1978).
deermice has 38 deermice whereas
  Perom had 36 deermice
  (Perom has been withdrawn.)
  In deermice the two semi-adults have been classified as adults.
  The sex variable has 1 for female, and 0 for male.