38 THE TONER LECTURES. 



1. The Middle Turbinated Bone. 



The middle turbinated bone is divided into two parts — an ante- 

 rior one-tiiird and a posterior two-thirds, nearly. The anterior part 

 is best seen when the nasal chamber is examined from in front, and 

 the posterior part is best seen from behind. 



The anterior third. This portion is a plate of bone which I'anges 

 parallel to the perpendicular plate of the ethmoid bone or is de- 

 flected outward at an angle. The free lower border may be abruptly 

 bent in or out. The entire anterior part may become inflated. It 

 is often of greater density than the posterior part (is often covered 

 with spines or is greatly roughened), and may be separated there- 

 from by a decided change in the inferior contour-line. At times a 

 groove cuts off" the anterior from the posterior part. This was well 

 seen in the skull of an Ottawa Indian.^ 



In the infant the anterior part is always thin and compressed. 

 It is parallel to the perpendicular plate, as above described. The 

 same disposition exists in many of the skulls of later childhood and 

 in those of adult life. Out of 188 skulls in which the anterior part 

 was examined the plates were as given in 70. 



The inferior or free border may be flat and wide, so that the ap- 

 pearance of the part might be compared to a w'edge whose apex is 

 directed upward. Of this variety 60 examples were observed. 



Instead of being flat and wide the inferior free border may be 

 bent abruptly upon itself or may present an acute projection which 

 is directed either inward or outward. Eleven examples of such 

 conformation can be cited. They were distributed among the races 

 as follows : Seven of Peruvian^ one each of German^, ancient 

 Roman\ Iroquois^ and Mexican'' origin. 



It is an interesting fact that no example of median inflection of 

 the lower border was noticed in the examination made of 78 negro 

 skulls. 



iNo. 1009. 2Nos. 957, 30, 228, 1432, 100, 1475, 631. ^^o. 1190. 

 *No. 248. &No. 119. «No. 1015. 



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