Hemichordata is a phylum of deuterostomeanimals, generally considered the sister group of our own, the Chordates. They date back to the Lower or Middle Cambrian and include an important class of fossils called graptolites, which went extinct in the Carboniferous. Modern forms are marine worms, commonly called acorn worms. They are divided into two classes: the Enteropneusta[?] and the Pterobranchia[?].
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... Hawaii), he contracted the disease, from which he died at the colony.
He is the patron of lepers and outcasts, and was recently made the patron of AIDS patients. The ...