228 Mammalia. 



congeries of nine ossicles more or less consolidated, arranged 

 in four pairs, the ninth piece being represented by the *body ' 

 or Basi-byal bone. The first pair, the Stylo-hyalSj immediately 

 internal to the posterior border of the ramus of the jaw, have an 

 enormous longitudinal development, being also somewhat 

 hammer- shaped and compressed laterally; their peculiar 

 figure being due to the presence of two apophyses at the 

 temporal extremity, by the superior of which the bony chain 

 is connected by a short ligament with the cranium. The 

 second pair, or Epi-hyaky are intercalated between the first 

 and third pair of ossicles ; the third pair (placed nearly 

 vertical) make a right angle with the first pair (which lie 

 horizontally forwards), and the second pair fill up the apex of 

 this angle, which is directed forwards. The third pair, or 

 Cerato-hyalSy have a nearly vertical position when the head is 

 raised. The body of the hyoid, or Basi-hyal, of a triangular 

 form, is placed below the cerato-hyals, and anterior to the 

 greater cornua or thyro-hyals. This fourth pair, the Thyro- 

 hyals, articulate to the extremities of the lateral apophyses of 

 the Basi-hyal, and lie nearly horizontally backwards, the 

 whole series forming on each side a figure like the italic S 

 sloping the wrong way. 



In Man, 



The Stylo -hy ah are represented by the ' Styloid process of 

 the temporal bone' ; the Epi-hyals by the ' styloid ligament'; 

 the Cerato-hyals, by the * lesser cornua ' ; the Basi-hyal by 

 the 'body '; and the Thyro-hyal by the 'greater cornua.' In 

 the Ruminant, the so-called ' greater cornua ' (of anthropoto- 

 my) are subordinate to the so-called ' lesser cornua ' in the 

 extent of their development. 



Removal of Parotid Gland ; and Dissection or 

 Stylo-Glgssus, Genio-Hyo-Glossus, and Genio-Hyoid 

 Muscles ; and Hypo-Glossal Nerve. The Student should 

 now remove the posterior part of the Parotid Gland along 



