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Show 478 DR. A. MACALISTER O N G L O B I O C E P H A L U S SVINEVAL. [May 9, head is rotated a little, so that the under surface of the lower jaw is turned forwards ; and the tongue is removed ; the latter was gone before the animal was submitted to m y notice.) The observations which I have subjoined may be grouped into three series : 1st, regarding the anatomy of the pharynx and larynx ; 2ndly, regarding the spinal muscles ; and 3rdly, regarding the structures forming the anterior extremity. Globiocephalus svineval. a. Scalenus posticus, b. Scalenus medius. c. Scalenus anticus. d. Trachelo-mastoid. e. Rectus capitis posticus major. /,/. Stylo-keraticus. g. Squamo-keratic joint, h. Stylo-pbaryngeus. i. Carotid artery. Jc. Sterno-thyroid. I. Thyroid cartilage, m. Front of same. n. Thyro-hyoid. o. Posterior cornu of hyoid bone. p. Hyo-keratic. q. Superior constrictor, r. Pterygo-keratic. s. Superior constrictor, t. Stylo-hyoid. The anatomy of the pharynx differs in many respects from that of Balcenoptera rostrata, and likewise from that of Delphinus and Phoceena ; in general, however, its modes of arrangement are more closely allied to those of the latter species than to those of the former. The pharynx is a wide ovoid bag with a large anterior opening communicating with the mouth, from which, however, it was separated by a thick round crescentic fold, which bounded the isthmus faucium upon three sides, and was attached to the base of the tongue below by the extremities of its cornua. This fold was smooth, but showed no trace of a uvula in its centre; but on dissecting from its surface the mucous membrane, a thick sphincter isthmi faucium or palato-glossus muscle was brought into view. This muscle, in common with its fellow of the opposite side, arose from the middle line of the velum pendulum palati, and was inserted into the side of the base of the tongue ; this muscle, when it acted, was capable of occluding perfectly the oral aperture of the pharynx, a condition of probable occurrence in the respiratory actions. The openings of the posterior nares passed upwards and forwards from the pharyngeal cavity above and behind the opening into the mouth ; these apertures were separated from each other by a septum, which did not extend as far backwards as the lateral boundaries of |