478 DR. A. MACALISTER ON GLOBIOCEPHALUS 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 my notice.) 



The observations which I have subjoined may be grouped into 

 three series : 1 st, regarding the anatomy of the pharynx and larynx ; 

 2ndly, regarding the spinal muscles ; and Srdly, regarding the struc- 

 tures forming the anterior extremity. 



Globiocephalus svineval. 



a. Scalenus posticus, b. Scalenus medius. c. Scalenus anticus. d. Trachelo- 

 mastoid. e. Eectus capitis posticus major. /,/. Stylo-keraticus. ^. Squamo- 

 keratic joint, h. Stylo-pliaryngeus. i. Carotid artery, k. Sterno-tliyroid. 

 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 diifers 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 sepa- 

 rated 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 com- 

 mon 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 oc- 

 cluding 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 



