The lymphoid tissue that extends from the cecum is known as the vermiform appendix.
The vermiform appendix is a small, tube-like structure attached to the cecum, which is the beginning of the large intestine. It has been traditionally viewed as a vestigial organ, but recent research suggests that it may play a role in the immune system. It is thought to contain lymphoid tissue that contributes to the production of immune cells and helps in the maintenance of gut flora.