CHAP. IX.] 



TEETH I GORILLA. 



203 



Supernumerary molars. 



*182. Specimen having m i behind and in series with the others 

 on both sides in lower jaw and on right side in upper jaw. On 

 left side both teeth are square and somewhat worn, but the 

 right m* is a curious conical tooth. Gallery of P. M., A, 505, 

 described by Gervais, P., Journ. de ZooL, in. p. 164. PL 



183. Two cases of four molars in each upper jaw. Magitot, Anom. du 

 syst. dent., p. 100, PL v. tig. 8. [Of these one is in collection of Dr 

 Auzoux; the other is No. 121 in P. M., but as I did not see it when 

 examining the collection it is not reckoned in the statistics given 

 above.] 



Similar case, Hensel, Morph. Jahrb., v. p. 543. 



184. Specimen having supernumerary molar which had not quite pierced 

 bone [no statement as to position]. Wyman, Jeffries, Proc. Boston 

 ]S T . H. S\, v. p. 160. 



185. Specimen having extra molar in crypt on each side in upper jaw 

 behind m 3 . L. M., 3. 



Super n umerary incisor. 



Fully adult male from Congo having an extra incisor in lower 

 , There are thus five incisors in lower jaw (Fig. 36), of which 



* 



186. 



jaw 



Fig. 36. Lower incisors and canines of Gorilla No. 186. .r, y and z are three 

 central incisors. The upper figure shews the tooth y as seen from the side. 

 (Specimen in Coll. Surg. Mus., 21, A.) 



one, presumably the supernumerary, stands almost exactly in the 

 middle line. This tooth is turned half round, so that the plane 

 of its chisel stands obliquely. The teeth are all well formed 

 and none belong to the milk-dentition, for the milk-teeth are 

 much smaller and of different form. I did not succeed in 

 satisfying myself that the central tooth is certainly the super- 

 numerary. The second incisors are in place on each side and 

 are quite distinct, and the right first incisor is similarly normal. 



