In his poem "To a Butterfly," William Wordsworth uses numerous visual images but his speaker does not actually describe the butterfly that they are addressing. Imagery is a literary device in which the author refers to any or all of the five senses to create a memorable impression. Vision is the primary sense to which Wordsworth appeals in this poem. He also uses the sense of touch in the last two lines.

As the poem opens, the speaker pleads with the butterfly to stay and not fly away. In line 2, the sense of vision is referenced:

A little longer stay in sight!

A second visual image occurs in line 4, when the speaker mentions the nearby presence of the butterfly, and asks it to continue to “float” there. The reason that the speaker wants it to stay close have to do with a memory that the insect evokes. This is specifically identified as a visual image, which has strong emotional and familial associations:

Thou bring'st …

A solemn image to my heart.

The speaker goes on to elaborate this memory image, which consists of them chasing butterflies with their sister during “days [of] … childish plays.” The description notes the differences between the approaches of the speaker and Emmeline, the sister. The speaker was bold in pursuing the butterflies, while Emmeline was cautious. In the last two lines, Wordsworth introduces the sense of touch. The speaker notes that the sister

Feared to brush

The dust from off its wings.