308 report— 1846. 



The bones of the face are reckoned as fourteen in number, viz. — 



The two malar (26) ; 



The two maxillary (21, 22) ; 



The two palatal (20) ; 



The two nasal (15) ; 



The two turbinal (19) ; 



The vomer (13), and 



The mandible (29-3?.). 

 The detached portion of the hyoid arch (40, 41) and its appendages (47), 

 together with the whole of the scapular arch and its appendages, are excluded 

 from the category of the bones of the head. 



The natural classification of the bones of the human skull appears to me 

 to be, first into those of 



The Endo-skeleton, 



The Splanchno-skeleton, and 



The Exo-skeleton. 

 The primary division of the bones of the endo-skeleton is into the four seg- 

 ments, called 



Occipital vertebra, N 1, H 1 ; 



Parietal vertebra, N 11, H 11 ; 



Frontal vertebra, N in, H in ; 



Nasal vertebra, N iv, H iv. 

 These are subdivided into the neural arches, called 



Epencephalic arch (1, 2, 3) ; 



Mesencephalic arch (5, 9, 7, s); 



Prosencephala arch (9, 10, 11 and 12) ; 



Rhinencephalic arch (13, 14, 15) : 

 and into the haemal arches and their appendages, called 



Maxillary arch (20, 21 and 22) and appendages (24, 26, 27) ; 



Mandibular arch (28, 29-32) (no appendage) ; . 



Hyoidean arch (3s, 40, 41) and appendages (4g) ; 



Scapular arch (51 and 52) and appendages (53-5S). 

 The bones of the splanchno-skeleton, are 



The petrosal (16) and otosteals (u>')*; 



The turbinals (is and 19) and teeth. (The sclerotals retain their primitive 

 histological condition as fibrous membrane.) 

 The bones of the exo-skeleton, are 



The lacrymals (73). 



* These ossicles are described by most anthropotoraists as parts of the ' temporal bone.' 

 " Os temporum infantis magnopere ab osse temporum adulti differt ; labyrinthi et ossiculorum 

 auditus fabrica absoluta est," says Soemmerring in the classical work before cited (t. i. 

 p. 132). The signification of the differences between the fcetal and adult human temporal 

 bone, which the great anthropotomist truly regarded as so remarkable, is made plain by 

 anatomy ; which shows the bone to be an assemblage of several essentially distinct ones, and 

 at the same time exposes the character .of that singularly heterogeneous assemblage and 

 coalescence of osseous elements to meet the exigences of the peculiarly developed frame of 

 man. What the ' ossicula auditus ' are, is a problem which still awaits careful additional 

 research in the embryonic development of the haemal arches of the cranium, for its satis- 

 factory solution. The question is not, of course, whether they are dismemberments of the 

 ' temporal bone,' since this has no real claim in any animal to an individual character ; but 

 whether the ossicles of the ear-drum in mammals are to be regarded, like the pedicle of the 

 eye-ball in the plagiostomous ashes, as appendages to a sense-organ, and thereby as develop- 

 ments of the splanchno-skeleton; or whether they are, like the tympanic ring, modifications 

 of the tympano-mandibular arch. The reasons are adduced in the Chapter on ' Special 

 Homology' (p. 235) which have led me to view them as peculiar mammalian productions 

 in relation to the exalted functions of a special organ of sense. 



