418 CRANIA FROM THE MOUNDS OF FLORIDA. 



cult to account for the absorption of the bones as a result of the accident. After 

 noting the increased width between the orbits and the depression of the nasal bones, 

 the nasal chambers should be inspected through the choanae. As a rule the middle 

 turbinal will then be seen to be set well off on the outer side of the chamber and 

 to retain a large bulla. 



The region of the anterior nasal aperture demands a few words. I shall name 

 it in this essay the nasal vestibule, since it enters into the composition of the floor. 

 I propose calling the rounded elevation on the floor in advance of the incisor fora- 

 mina the incisor eminence. The continuation of the lateral margin of the anterior 

 nasal aperture to the anterior nasal spine becomes the basal marginal line, but since 

 it always defines the alveolus superiorly, I have ventured to call it the alveolar 

 line. Should a so-called prenasal fossa be present it lies between the incisor emi- 

 nence and the alveolar line. Both the incisor eminence and alveolar line are, as a 

 rule, complementary of one another. Extending from each to the incisor crest or 

 anterior nasal spine delicate ridges are often found x 



The measurements of the ascending and horizontal limbs at the nasal vestibule 

 afford interesting characters. In Man ~ and the apes the ascending limb is early 

 united with the maxilla. Yet its position can be closely approximated by measuring 

 the height of the side of the anterior nasal aperture. The horizontal limb is the' 

 inferior border of the aperture, and when the skull is seen in profile the forward 

 extension of the crest of the premaxilla can be measured by the degree that it pro- 

 jects from this line. As is known, this region of the skull is exceedingly variable 

 and accurate method is needed by which it can be studied. 



Topinard 3 recognizes three types of conformation of the anterior nasal aper- 

 ture (here called the nasal vestibule) : one in the form of the figure of the heart 

 on the playing card, instanced in European races ; one with blunt border, base 

 spread out and with absence of nasal spine, instanced in African races ; one with 

 two digital depressions, instanced in the Chinese. Welcker proposes the term 

 pteleiform (elm-leaf like) opening for extreme variations of No. 1 of Topinard. 

 The word is peculiarly apt, for the asymmetiy of the anterior nasal aperture as seen 

 in many modern European skulls and those of ancient Etruria, is precisely like 



1 That the incisive portion of the superior maxilla is homologous with the premaxilla of quad- 

 rupeds is a statement so well sustained that it often comes convenient to use the term in description. 

 The incisor crest might become without violence the premaxillary crest, the margin of the vestibule that 

 lies below the nasal bones is said to be composed of the premaxilla, and the premaxilla may be said to 

 have an ascending or nasal limb, and a horizontal or incisor limb. These terms are available in descrip- 

 tions of the human skull. 



" In Simia the floor of the vestibule is flat ; in Gorilla it is greatly raised at the incisor eminence 

 and inclines gradually toward the alveolus, which is without a limiting line ; in Anthropopithecus the 

 incisor eminence is rudimental, but the highest point of the floor is anteriorly near the small alveolar 

 line and declines abruptly downward and backward to the incisive foramina ; in Hylobates the floor is 

 much the same as in the last-named genus, but the sides form oblique thickened borders, giving charac- 

 ters which are quite different in kind from those seen in other apes of the group. In no ape is the spine 

 or incisor crest developed, but so far as the other features of the floor are concerned the variation of the 

 vestibule can be considered to be atavistic. 



3 L' Anthropologic 1876, 227. 



