This document discusses the phylogeny and affinities of Balanoglossus, which is a member of the phylum Hemichordata. It examines Hemichordata's relationships to Chordata, Annelida, and Echinodermata based on morphological and anatomical similarities and differences. While Hemichordata shares some key characteristics with Chordata, such as the presence of a notochord, dorsal nerve cord, and pharyngeal slits, it also displays important differences. Comparisons are also made between Hemichordata and Annelida based on their segmented worm-like bodies, and between Hemichordata and Echinodermata primarily through similarities seen in their lar