I'll) MKK1STIC VARIATION. [I-AKT I. 



I Variation in I -rs and Canines. 

 A. Wn.i. < '\NIIU. 



No ' ise of extra incisor known t<- me. 

 I 'wo cases of absent incisor, viz. 



'2 In [Canis] Vulpes pennsylvanica, IJiit. Columbia, having 

 {_ ' 



' : apparently f 1 has not been present on either side. B. M., 



I K):i. b. 



21 1 Canis vulpes: nlv "> incisors in lower jaw, with no trace 

 'of al\.-oln> t'..r the sixth. SCHAFF, E., Zunl. Gart., 1887, xxvm 

 P. 27". 



I-i. DOGS. 



212 Dog i r. -milling Bloodhound) : four incisors on each side in 

 upper jaw. Tli.- .-\ternals, i 3 , normal, but no evidence as to which 

 of ih' "tluT teeth supernumerary. Leyden Mus. 



2lo. Thibetan Mastiff, Nepal: sockets for four teeth on each side in 

 pmx. Teeth ,-,11 Li'"iie. Alveoli of two sides nearly symmetrical. In 

 absence ' the t.-,-tli it cannot be positively stated that this is not a case 

 ..I persistent milk t.-.-tk but this seemed unlikely. L>. M., 166, //. 



-I I- Mastiff: fmir ti-t-th on eacli side in front of canines; from form of 

 teeth probably case of persistent milk-canines. Lower jaw gone. O. .M.. 



171'.'. 



'1 1 5. Dog : on ri-lit. sockets for three teeth in addition to >'[ which is in 

 ]>l;i<T. Tli'-" tlu-f >,7.-'/.x nil. smaller titan the normal ones, and socket 



t"i n|.|M-r ii-lit c;iiii;ic .-ilsci slightly reduced in size. Odont. Sac. J ///.. 



21(i. Dog: .-in.-ill -kull in my ]"-., -.ion, has in ]>lace of right ' :; ln-<, 

 nli; nil, /,/// /// //,. sown level, li\iili-d li\- a thin bony septum, the one 

 internal t.. tin- ntlirr: left ^ is in place and normal: lower jaw gone. 



217. Ann.ii'j :U"> Dogs' skulls tour had extra upper incisor on one 

 -ide, and om- >knl| ha.l p.-rt'.-ct ly tormeil fourth upper incisor 

 "ii li'it/i <ide>. 'I'liis lootli smaller than third incisor. HEXSEL, 



('. "'!!-. S '-I'al eases of 7 or S ineisol's in U])per jaw, teelh 

 In-ill- ii-uallv a>\ nunetrieal. Nl-:il HINC. N/V;A. inif. /'/'. Bed., 1S>>2 



I 1 - ' 



In lower jaw sudi cases inueh rarer. Superman, lower in- 

 cisor on Hi,,- >ide. one ea-e [ .' in (i.')0 skulls], N KH it I NG, ibid. ; also 

 Dog (chien chinois-japonais), 4 im-isors in each lowi-r jaw. 

 M.\;rn >'i. J - >/. dent., \>. M. 



( 'ase of' ,//'n'(/! incisor. 



Bulldog: li-lit | with very wide crown ; main cusp partially 

 bitid as if Intermediate betueen single and double condition, 

 Morph. /.nl>. ( Cambridge. 



Siiinhu <-!i-.- kinilly si-nt t inr liy l'i,,f. (,. I',. 



