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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXV. 



distad from them slants forward from the forehead proper, showing 

 that the convexity of the frontal is not only lower, but also relatively 

 somewhat more posterior than usual. The frontal sinuses are of only 

 moderate size, the total length of the right cavity being 1.7 cm., its 

 greatest antero-posterior diameter a little over O.G cm. There is no 

 dorsal metopic crest in this case and the ventral one is of subaverage 

 dimensions. The external bulge of the forehead is really quite fair, 

 the defect being only the lowness. 



Here then is a case in which a low forehead is a separate condi- 

 tion, independent of and not materially affected by any factors proper 

 to the lower anterior portion of the frontal bone. 



Side view of the Missouri skull. 



The two cases reported here are in the line of demonstration of the 

 fact that the low or sloping appearing forehead is not morphologic- 

 ally a simple feature, due always to the same causes and having but 

 one significance. They make it clear that there are at least two 

 general, though perhaps in the end not unrelated, categories under 

 which this peculiarity may be classed, one embracing the cases due 

 to excessive development of the forestructures of the forehead proper, 

 the other including those of defective development of the forehead 

 part of the frontal bone itself, irrespective of anything else. When 

 both conditions coexist, and that seems to be most often the case, they 

 accentuate each other, and in extreme cases the results are such 

 human cranial forms as the Neanderthal, Spy No. 1, or No. 8 from 

 the Gilder mound in Nebraska. 



