200 MKKLSTIC VARIATION. [PART I. 



group of mammals of which I have been able to examine a con- 

 siderable numb. T. lii different collections 14'2 normal adult skulls 

 were BCCE and 12 cases of extra teeth. Of these one was a case 

 of extra inei-or (dorilla, No. 186), one of anomalous teeth (Gorilla, 

 \.< I ^7 i. ami the remainder molars. Thus far therefore there are 

 1 1. -aily s per i -i nt. cases of extra teeth. This figure is remarkable 

 in roinpari-on with the rarity of such cases in nyldbates (51 skulls 

 ii. all normal), and the like rarity in other Old World monkey- 

 > li'.'i normal- ami "1 cases of extra teeth). 



Simla satyrus (Orang-utan). 

 \"iinal adult skulls seen, 5'2. 



wnumerary molars. 

 liii. Adult mall- having additional posterior molar (m 4 ) behind and 



in series \\ith the normal teeth, on both sides in upper jaws and on 

 left -id.- iii lower jaw. In each case the m* is rather smaller than 

 in . hut all are well formed, having each four cusps and the normal 

 "iiijil. nifiit of l'aii;4-, viz., one in front and one behind in the 

 |.I\\,T jaw. ami two mi outer and one on inner side in upper jaw. 



< in ri_dit .ide of lower jaw there is no trace of additional molar, 

 thoii-h there is almost as much room for it as on the left side. 



< '. M.. I h;u. It. described by HUMPHRY, G. M., Jour. Anat. P1,<i*.. 

 L874, p. l-H). Plate. 



''" l-'i-iiiali- (]'.. i-iico) having six cheek-teeth in each upper jaw and in 

 li-lit I.AVI-I- jaw [doubtless a case like the foregoing] mentioned l>y 

 I'l MI-. \\ .. Sitzungsb. n<itnrf. Fr. Berlin, 1872, p. 76. 



His. Sj.rcinicn \\ith largr alveolus on each side for m*. L. M., 24. 



lii!'. Sjierinicn ( Korn. -o) having ^ in right lower jaw, behind and in 

 lee with the nnrnial teeth. The tooth is of rather small size, but is 

 regular in jiu-itiun and t'-.r'ii. 15. M., 3, m. 



17". Sj.eeini.-n haxin- a riglit ^ more than half the size of ri>. U. C. M., 

 I-. 253. 



171. Specimen having supernumerary molar on each side in lower jaw. 

 M\M:K. Arch./. A'./////- : /.. ls(:', 1. \v. p. 356. 



172. Similar case. FiT/iNcr.K, Sitzungsb. tn-if/i.nnt. CL Ak. Wien, 

 1853, i. ]. i:;6. 



similar case. I'.in in.. /.,>, Kenntniss > - n,-<in<jk<n>f^, ^i< v n, 1856. 

 ' refen t.. the ease des.-ril>ed l.y FIT/.INCI.I;. \ 



S|,eeinien "remarkable t'..i- absence of tin- upper right third 



m. ilar and f.,r absence "f na-al bones, \\hich are gn-atly reduced 



in some other specimens." C. S. M.. 44. See Catalogue Mus. Coll. 

 >'///. l.s.s^ Tlie ,,tlier teeth aiv all normal and fully formed. 



Variations in position /tr,-flt. Th..ugh not directly pertaining 



to the sul.jeet her,- e,,| lH dered. the following examples'of consider- 



