X SKULL 477 



between the frontal and maxilla, is a small bone,the lachrymal* 

 (Fig. 122 A, Icr) with a notch near its outer border through 

 which the naso-lachrymal duct passes (compare p. i86.) 



As in the frog, the chief bones of the upper jaw on either 

 side are t\ie premaxilla * [p. max) and the maxilla* (^max), 

 and nearer the middle line are the palatine* {pal) 

 and pterygoid* {pt)'- in the embryo the position 

 of the two last mentioned bones is taken by 

 cartilage representing the upper jaw of the dogfish (com- 

 pare Figs. 103 and 9). The premaxillge, in which the 

 sockets for the front or incisor teeth are situated, form the 

 anterior boundary of the snout, and articulate with one 

 another in the median line and with the maxilla behind : 

 each gives off a nasal process passing backwards between 

 the nasal and maxilla to the frontal, and a palatine process 

 {pal. p. max) extending backwards along the palate in 

 contact with its fellow of the opposite side. The maxilte 

 are large and irregular bones, parts of the sides of which are 

 fenestrated, and in which the cheek-teeth are situated. From 

 the inner and inferior edge of each, opposite the first two 

 cheek-teeth, a horizontal palatine process {pal. max) is 

 given off, which, articulating with its fellow of the opposite 

 side, forms the anterior part of the bony support of the 

 hard palate — this is of much less extent in the rabbit than 

 in most mammals : from its outer side arises a zygomatic 

 process {zyg. max) which forms the anterior part of the 

 strong zygomatic arch extending below and externally to the 

 orbit. 



The palatines are thin, nearly vertical, bony la- 

 mina, internal to the maxillae, to which they are at- 

 tached in front, while above they join the presphenoid 

 and the pterygoid process of the alisphenoid. They 

 bound the passage of the internal nostrils, and from the 



