Thoreau writes in his journal:
The skunk-cabbage in full bloom under the Clamshell Hill . . . I see but on tortoise (Emys guttata) in Nut Meadow Brook now . . . Tried to see the faint-croaking frogs at J. P. Brown’s Pond in the woods . . . Did not see frog spawn in the pool by Hubbard’s Wood.