glands, with their ducts opening out between the epithelial cells of the mucous membrane. There are two kinds of glands in this region, which have been described by Klein[21]--viz. serous and mucous glands. [Footnote 19: Haenle, _Anatomy des Menschen_, vol. ii.] [Footnote 20: Haenle, _loc. cit._] [Footnote 21: _Loc. cit._] This cavernous erectile tissue is most abundant at the lower portion of the septum and of the lower turbinated bones; and, although it has been recognized and described as true erectile tissue by Haenle, Virchow, and others, yet to Bigelow of Boston belongs the honor of having first called attention to the part which this tissue plays in nasal diseases. He gave to it the name turbinated corpora cavernosa.[22] The expansion of the nasal cavities formed by the alæ of the nose is termed the vestibule, which is lined with pavement epithelium and forms the entrance to the cavities proper. The naso-pharyngeal cavity extends from the posterior ends of the turbinated bones and the edge of the vomer to the line where the velum palati touches the pharyngeal wall during the act of deglutition or phonation. In this cavity we find the openings of the Eustachian tubes, two crater-like elevations, with a pit-like depression of variable size and shape, one on either side; and a collection of glands with a central duct-like opening disposed on the roof and posterior wall of the cavity. This gland was named by Luschka[23] the pharyngeal {36} tonsil. The openings between the edge of the vomer and the lateral walls of the naso-pharyngeal cavity are termed the posterior nares. [Footnote 22: _Boston Med. and Surg. Journal_, April, 1875.] [Footnote 23: _Der Schlundkopf des Menschen_.]