Final answer:
The element of modernist poetry evident in the excerpt is imagery.
Step-by-step explanation:
The element of modernist poetry that is evident in this excerpt from "The Negro Speaks of Rivers" by Langston Hughes is imagery.
Imagery is the use of descriptive language that appeals to the senses to create vivid mental images for the reader. In the excerpt, Hughes uses vivid imagery to describe his experience with rivers. He compares the ancientness of the rivers to the flow of human blood in human veins, emphasizing their timeless and deep significance.
This excerpt does not exhibit symbolism, as it does not use objects or elements to represent abstract ideas or concepts. It also does not display the stream of consciousness, as it is not a flow of the character's thoughts and feelings in a continuous and unfiltered manner. Lastly, there is no alliteration in this excerpt, which refers to the repetition of initial consonant sounds in neighboring words or syllables.