CHAP. IX.] 



TEETH I CANID.E. 



221 



In addition to these, 



wi 3 and m* absent on both sides, 1 case. 



This was the only case in 860 skulls of Canis, of which about 650 

 were Dogs. The formula in it is thus that of Otocyon or the fossil 

 Amphicyon. Nehring, Sitzb. naturf. Fr. Berlin, 1882, p. 66. 



In 216 skulls seen by me there were 8 cases of extra molars, viz. : — 



258. Sheep dog : left m 3 . C. S. M., 587; Bulldog : left m 3 . B. M., 

 166 s; Dog from New Zealand, having left m\ left m* being larger 

 than right m». C. M., 1000; Bhotea Mastiff: m+ on right B. M., 166, 

 f.; Pointer: lefty. C. M., 1000, A; Dog: right Ji? Carnb. Morph. 

 Lab.; Pariah : m 4 has been present on both sides, also a small stump 

 below ^ and p 2 , possibly part of a milk-tooth. B. M., 166, <l. 



259. Mastiff: supernumerary m 4 on right. The right m? materially 

 larger than left ^ (Fig. 45). C. S. M., 555. 



right 



left 

 reversed 



200. 



261. 



Fig. 45. Posterior molars of lower jaw of Mastiff No. 259, having an extra m 4 

 on the right side. Right m? is materially larger than left ^i. 



Dog, large size, supernumerary m* on right side. On both sides 

 m? is two-rooted 1 and of large size. Leycl. Mas., 258. 



Windle and Humphreys, P. Z. S. } 1890, p. 27, give an account of 

 extra molars in the Dog, speaking of upper jaws only, and some of the 

 foregoing are mentioned by them. As they do not specify the collec- 

 tion in which each is found the identity of the cases is not easy to tell. 

 The following cases given by them are, I believe, all in addition to 

 those already specifiecl : — Bulldog, Lurcher, Pointer and Terrier, 

 m? on both sides. Bulldog w 3 on left side; Esquimaux, Pug, 

 Spaniel, West Indian Dog, »f on right side. 



Coach-dog : ?/7 4 on both sides, Magitot, Anom. Syst. dent., p. 103. 



Absence of Molars. 



262. Dog: in 345 skulls the following seen : ?«'- and ^ absent on both sides, 2 cases; 

 ^2 and ^a absent on both sides, 1 case ; ^ absent on both sides, 25 cases ; ^ absent 

 on one side, 9 cases. Hensel, /. c. 



In 216 seen by me the following occurred: ^3 absent on both sides, 7 cases; 

 C. M., 993 and 978; C. S. M. {Store), 65 and 67; two skulls marked " Skye Terrier/' 



1 It generally has a simple, conical root, but not rarely it has an imperfectly 

 divided root, e.g. Newfoundland dog, O. M., 1778. 



