Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Waldeyer''s tonsillar ring (or pharyngeal lymphoid ring) is an anatomical term describing the lymphoid tissue ring located in the pharynx and to the back of the oral cavity.It was named after the nineteenth century German anatomist Heinrich Wilhelm Gottfried von Waldeyer-Hartz.The ring consists of (from superior to inferior): Pharyngeal tonsil (also known as ''adenoids'' when infected) Tubal tonsil (where Eustachian tube opens in the nasopharynx) Palatine tonsils (commonly called "the tonsils" in the vernacular, less commonly termed "faucial tonsils") Lingual tonsils.