WHOLE VOL. SKELETAL REMAINS OF EARLY MAN HRDLICKA 83 



for comparison, coming much nearer the alveoh in some human mandibles with 

 macrodont teeth. The total length in the median line of the three alveoli is 

 3.9 cm. ; in the Mauer jaw it is 3.8 cm. ; in some modern human jaws with large 

 teeth it ranges from 3.6 to 3.9 cm. ; ^ in the available male chimpanzees it varies 

 from 3.0 to 3.4 cm.;" in chimpanzee females from 3.1 to 3.25 cm. The size of 

 the three molar alveoli in the Piltdown jaw is plainly not chimpanzee-like, but 

 stands close to early and macrodont recent human. 



The breadth of the molar alveoli in the Piltdown mandible is just 10 mm. 

 for each alveolus. This is also larger, and that by from 0.5 to 2.5 mm., than 

 that of corresponding alveoli in any of the available chimpanzees,^ but is 

 equalled or closely approached in the Mauer (Mi, 10; M2, 10.5; M3, 10 mm.) 

 and in some modern human jaws with large teeth (Australian, No. 255,715, 

 Mi, 10.2; M2, 10.2; M3, lo.i mm.; New Britain, No. 226,107, Mi, lo; M2, 10; 

 M3, 10 mm.; Arkansas Indian, No. 262,587, Mi, 10; M2, 10; M3, 10 mm.; etc.) 



The dimensions of the alveoli in the Piltdown jaw, together with the two 

 remaining teeth (rMi, M2), show that the teeth were large. They were larger 

 than any chimpanzee molars that are available for comparison. The Piltdown 

 man or woman, like the jaw of Mauer and probably also other early human jaws 

 (La Chappelle, La Quina), came therefore in all probability from a macrodont 

 ancestry. As the bone mass and the musculature of the jaw are both reduced, 

 the size of the teeth cannot be regarded as an individual peculiarity. 



The two teeth themselves are naturally of much importance. They in a way 

 resemble both the molars of some chimpanzees and those of some men. But they 

 possess important characteristics that separate them from the ape teeth and 

 approach them closer to human. They are somewhat more dolichodont (rela- 

 tively long and narrow) than most human molars, but individual human teeth 

 equalling them occur. In chimpanzees dolichodont molars are more frequent 

 though there are also many exceptions ; but in general the type of the crown 

 in the chimpanzee is somewhat different. 



The two anterior cusps in each of the teeth in the Piltdown jaw were stout 

 and close together as in many human teeth. In the chimpanzees as a rule these 

 cusps are smaller and farther apart. 



In the chimpanzees the enamel part on the sides of the molars is lower (less 

 in height) than in man; in the Piltdown jaw the conditions are about the same 

 as in man. 



In the Piltdown jaw, as occasionally in man, the enamel on the outside and 

 slightly also on the inside extends in a pointed way towards the notch between 



^Australian (U. S. N. M. Cat. No. 255,715), 3.9 cm.; Peruvian Indian (No. 

 293,249), I"? cm.; New Britain (No. 226,107), 2s-(> cm. 



^ Males : U. S. N. M. Cat. No. 84,635 = 3.3 cm. ; No. 174,704 = ZZ cm. ; 

 No. 174,710 = 3.0 cm.; No. 176,226 = 3.1 cm.; No. 176,227 = 3.1 cm.; No. 

 176,228 = 3.3 cm.; No. 176,230 = 3.3 cm.; No. 176,235 = 3.3 cm.; No. 176,244 = 

 34 cm. 



Females: U. S. N. M. Cat. No. 176,700 = 3.25 cm.; No. 174,701=3.2 cm.; 

 No. 174,706 = 3.1 cm.; No. 176,229 = 3.1 cm.; No. 176,243 = 3.1 cm. 



'In the strongly developed male No. 174,699 the alveoli for the first and right 

 second molars just reached, 10 mm., but those for the other molars in the jaw 

 are slightly to markedly smaller. 



