Mammalia. Prohoscidia, 41 



the back part of the base forms the true brain case. The pneumatic 

 Maxillaries are remarkable for the large proportional size of their 

 alveolar part, in advance of which the bone extends upwards to be 

 wedged between the Frontal and Premaxillary, downward and for- 

 , ward to strengthen the socket of the Tusk, and lachward to form the 

 anterior pier of the Zygomatic arch and the lower part of the Orbit. 

 The pneumatic Premaxillary mainly consists of the part which 

 lodges the base of the great Tusk ; but its ascending portion reaches 

 the Prontal, and excludes the Maxillary from the Nasal. The 

 Upencephalic compartment of the cerebral cavity is wholly behind the 

 Pros- and Mes-encephalic ones, as is also the case in the Insectivora, 

 Cheiroptera, Eodentia, and Inenamellata. 



The Vertebral Column. The Epiphyses continue detached from 

 the bodies of the Yertebrae to nearly full growth : the Centra are 

 remarkably short for their breadth, especially in the Cervical region. 

 The first and fourth Dorsal are remarkable for the strength as well 

 as the height of their neural spines. There is no Anticlinal Terte- 

 bra in the Dorso-lumbar series. The first and second Rils are 

 almost straight, and expand to join their short sternal parts. Five 

 pair of ribs directly join the sternum, which consists of four bones. 

 IS'early two-thirds of the Caudal vertebrae are reduced to the centrum 

 alone. 



Anterior Appendages. There are no Clavicles : the Scapula is 

 broad and concave, and has thick epiphyses attached to the border ; 

 a process depends from the short pointed Acromion ; the Glenoid 

 cavity is shallow ; the Coracoid a mere tuberosity. The head of the 

 Humerus is sessile ; the great tuberosity rising above it and extending 

 antero- posteriorly ; each of these has a separate epiphysis. The 

 Radius, crosses obliquely in front of the Ulna to the inner side of 

 the Carpus, has its head wedged between two processes of the Ulna, 

 and has its expanded distal half attached by a ligament to the 

 Ulna. The Feet have five toes, which are outwardly indicated only 

 by divisions of the hoof. 



Posterior Appendages. The Ilium on each side is but narrowly 

 apposed, by the edge, to the three Sacral vertebrae, and stands out 

 from them so that its principal axis forms a right angle with the axis 

 of the Vertebral Column. The Ischia and Pules are short, and 

 form a symphysis, the axis of which is parallel with that of the 

 vertebral column. The Great Trochanter does not rise so high as 



