. Annual report of the Board of Regents of the Smithsonian Institution. Smithsonian Institution; Smithsonian Institution. Archives; Discoveries in science. 1010 REPORT OF NATIONAL MUSEUM, 1895. front half of the tongue the character of a double tubeJ The base of the tongue is formed by the soft, fatty, fibrous envelope of the basihyal, which stretches like a mass of india rubber when the tongue is pro- truded, and, like rubber, contracts when the tongue is retracted. Immediately in front of this is the dense cartilaginous sheath of the ceratohyals, forming the bulk of the tongue and practicall
. Annual report of the Board of Regents of the Smithsonian Institution. Smithsonian Institution; Smithsonian Institution. Archives; Discoveries in science. 1010 REPORT OF NATIONAL MUSEUM, 1895. front half of the tongue the character of a double tubeJ The base of the tongue is formed by the soft, fatty, fibrous envelope of the basihyal, which stretches like a mass of india rubber when the tongue is pro- truded, and, like rubber, contracts when the tongue is retracted. Immediately in front of this is the dense cartilaginous sheath of the ceratohyals, forming the bulk of the tongue and practically consisting of two portions—that investing the bony part of the ceratohyals and that surrounding their cartilaginous prolongations. The ditferencc between the character of the epidermis of these two parts is such tbat in badly preserved or slightly macerated specimens the anterior part may be slipped ofl" intact. If this is done, it will be found to be a hollow tube of cartilage, grooved along the middle above and below, and slightly grooved along the upper, outer surface. This tube is soon divided by a vertical partition, while a little more than halfway between base and tip the tongue forks, each branch continuing hollow for some distance. A fold, or flange, commences near the base of the tongue, on either side, and continues to the tip, growing wider and. Fig. 7. thinner as it proceeds, until along the branches it becomes a very deli- cate membrane. As previously stated, it is these two membranous portions which become rolled into tubes, and when the tongue of the humming bird is spoken of as being tubular, it is these branches which are meant. To say that the tongue consists of two iiarallel muscular tubes is quite erroneous, as is the statement that the tubular portion of the tongue is drawn back into a muscular sheath. It seems a little doubtful if the tongue of the humming bird can be a true suctorial tongue, for the tubes formed by the anterior part of the tongu
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