Haiku the colloquialism of the language and is closest to natural conversational rhythm, necessary to carry the weight of the hokku A haiku traditionally contains a "kigo", a word or phrase that symbolizes or implies the season of the poem and which is drawn from a "saijiki", an extensive but prescriptive list of such words. Kigo are often in the form of metonyms and can be difficult for those who lack Japanese cultural references to spot. The Bashō examples below include "kawazu", "frog" implying spring, and "shigure", a rain shower in late autumn or early winter. Kigo are not always included
Haiku theoretician F. S. Flint, who passed on Couchoud's ideas to other members of the proto-Imagist Poets' Club such as Ezra Pound. Amy Lowell made a trip to London to meet Pound and find out about haiku. She returned to the United States where she worked to interest others in this "new" form. Haiku subsequently had a considerable influence on Imagists in the 1910s, notably Pound's "In a Station of the Metro" of 1913, but, notwithstanding several efforts by Yone Noguchi to explain "the hokku spirit", there was as yet little understanding of the form and its history. R. H. Blyth