Four peculiar galaxies

These images from the KPNO 4-meter Mayall telescope show four different peculiar and interacting galaxies: NGC4656/7 in Canes Venatici, type Sc/Ir; NGC2545 in Cancer, type Sb; NGC3986/8 in Ursa Major, type S0; and NGC6621/2, also known as Arp 81 and VV247, in Draco, type Sb(pec).