Answer:
Haphazardly.
Step-by-step explanation:
The excerpt is taken from "The Cask of Amontillado" where the underlined word "promiscuously" is used for the bones laid on the earth that illustrates the meaning "haphazardly" as it forms a heap of some size. The tone of the sentence suggests that these remains cause walls of human remains that are aimlessly thrown which are 'promiscuous' for the nature that symbolizes "haphazard". Thus, the context of the underlined word is synonymous with 'haphazardly' or 'indiscriminate' that illustrates the threat to the environment caused by human remains and the piles of it.