56 



Soil f /icy fi ( yoss. 



are tlie "<la\ii;lit»-r " t^ftli alimtst i5<|Uiil in size to the remaining 

 imliviiluuls i)f the suric*. 



(III.) In f«»«ir of these five eases, on the above reasoning, the 



extra totith is aj'^arently the prochict of m. --. In one only 



(Xo. 324^') is it apparently the product of p.m. — . 



(IV.) In athlition t<. the above, there occur several instances of 

 wlmt, following the above suppositions, can only be regarded as 

 iilKirtive or incomplete division or ri-dnplieation of teeth. Such 

 aliortive reduplication may be of two kinds. 



(V.'i Kiiher it occurs (n) as if by some kind of sympathy in a 

 tooth closely related io an individual supposed to have undergone 

 rotlui>lic^»ti«>n, either on the opposite side of the same jaw or in the 

 opiK>sit.' i.aw. Thus in No. 3246 (a highly interesting specimen, since 



tl pre>cni.s the only instance of reduplication in p.m. — , — the only 



instance of complete reduplication on one side accompanied by only 

 alwrtive reduplication on the other — also the only instance of, in addi- 

 tion to the alMive, abortive variation in m. — — in which the formula 



i.s p.m. and m. '-^), all the first premolars being halfway along 



the road to division. Each, although singly rooted, is provided with 

 two, in most cases (piite distinct and perfect, crowns, and is grooved 

 along the most probable line of division into two teeth. 



(VI.) (ir (b) it may occur independently, as has happened in the 



cHMi of m. -^ of the same head (No. 3246), or in p.m. — , of No. 2. 



4 



(\II.) In addition to the supposed reduplication or splitting a 



vi-ry wide range of variation is observable in regard to the rooting 



10 teeth. Almost any of these, except the first premolars, 



may aj.iwar either with two ijcrfect roots or with a single root 



only. 



(VI II J l;ut between these forms there are many gradations 



^' *'*'• by llaltened single root.s — ilattened single roots grooved 



«i •> ...>• plane where a ili vision into two roots would occur— flattened 

 Mnglf rw.tH in which incii»ient division is indicated 1)V a terminal 

 notch and all .sUiges of development of this terminal notch, until it 

 >H-« ft rh.ft dc.pjy dividing the pillars of a fully developed 

 -luublc nM.t. The.st. gnidations are most ea.sily seen in the teeth of a 

 '•■ h.-ad. such .IS the lower mohirs of No. .S246 or of No. TOO; 



