388 Miscellaneous. 



The nares are terminal, divided, lateral, and arch forward in 

 front of the alveolar margin. The orbit of the eye is S inches behind 

 the extremity of the snout, nearly circular, and separated from the 

 temporal vacuity by the postfroutal bone. The postfrontal bones 

 converge backward along the parietal crest. The malar bone 

 develops a slight descending process on its inferior margin. There 

 is no interorbital septum ossified. The type species of C ynognathus 

 shows on the one side preserved a small postorbital foramen, com- 

 parable to that of Procohplion, and the author considers that the 

 enlargement of this foramen makes an essential difference in plan 

 between the skuUs of Teleosaurs and Theriodonts, and regards the 

 mammalian zygoma as resulting from the obliteration of the post- 

 orbital vacuitj' which defines the superior and inferior temporal 

 arcades in Saurischia and other Reptilia. 



In general structure of palate Ci/nognaiJius resembles Li/cosaurus. 

 There is no transverse boundary to the hard palate, but the palato- 

 nares are lanceolate. The author finds that the downward develop- 

 ment of the bones of the palate at the posterior borders of the nares, 

 while thoroughly reptilian, approximates to the condition in 

 mammals. 



The form of the lower jaw approximates to that of the older 

 mammals and lower mammalian types, leading to the conclusion 

 that the mammalian lower jaw consists essentially of the dentary 

 bone. The dentary bone is compared to that of Micronodon in form 

 and development of the angle of the jaw. 



The shoulder-girdle consists of a large scapula, small coracoid, and 

 compressed pre-coracoid. The scapula demonstrates the origin of a 

 spine like that of the scapula in mammals by outward development 

 of the anterior border of the scapula in reptiles. This spine is 

 defined by a prescapular development anteriorly. The spine may 

 have been originally a separate ossification, such as in Pareiasaurus 

 has been named epiclavicle. It terminates in an acromion which 

 is reflected forward. 



The humerus is imperfectly preserved, but has the distal con- 

 dyles well developed ; and tlie proximal crest has a form which is 

 seen in marsupials, but the articular head is transverse. 



The vertebral column measures 37 inches from the body of the 

 atlas to the last lumbar vertebra, and its total length is 45 inches ; 

 but the extremity of the tail is lost. There appear to be only six 

 cervicals defined by the form and direction of the transverse processes 

 for the tubercles of the ribs. The head of the rib is attached to 

 the iutercentral sutui-e, and in the first vertebra reaches the inter- 

 centrum. There are 29 presacral vertebrae, of which IS may be 

 counted as dorsal and 5 as lumbar. The most distinctive feature 

 of the vertebral column is the interlocking of the ribs in the lower 

 dorsal and lumbar region, where the ribs become transversely 

 expanded and anchylosed to the side of the centrum. The neural 

 arch in the lumbar region also interlocks by an arrangement 

 resembling the zygosphene and zygantrum of serpents. No dorsal 

 rib is completely preserved. 



