This plate depicts: a Roseate Spoonbill, an American Avoset, a Ruddy Plover, and a Semipalmated Sandpiper.
According to Audubon: "The Roseate Spoonbill is at once beautiful and bizarre... Thanks to conservation efforts, the species has recovered significantly from near-decimation during the plume-hunting era." http://birds.audubon.org/species/rosspo