TOOTH-GENESIS IN THE CANLDiE. 435 



its internal face which runs upwards, at the margins of the tooth, to the apex 

 of the crown. Between this tooth and tlie canine is a wide diastema. 



The canine is long, pointed, and recurved, and shows a similar condition of 

 the cingulum on its internal face. Between this tooth and pm.^ is a very wide 

 diastema. 



The first premolar is much reduced and with but a mere trace of an internal 

 cingulum. The posterior margin of the tooth shows a slight angulation which 

 in the more posterior premolars appears as a minute cusp. Between this 

 tooth and pm.^ is a distinct di't.stema. 



The second premolar is rather larger than the first and has two fangs. A 

 minute cusp is to be seen at the posterior border formed by the internal cin- 

 gulum which runs into it. The cingulum is also more noticeable on the inner 

 face of the anterior root ; that is, in the posioion of the Protocone. 



Slight diastema between pm.^ and pm.^ 



The third premolar has characters similar to those of the second but more 

 xnarked, as it is a somewhat larger tooth. 



The fourth premolar has a main cone with a well-marked cusp anteriorly 

 and another posteriorly to it. There is a very well-marked ridged cingulum 

 on the internal face of the main cone, which leads up to and forms the anterior 

 and posterior cusps. The Protococe is large, almost ms high as the main cone, 

 and placed in the same transverse line. It is diitinctly a cingulum-cusp. 



On the ridge of the cingulum, leading from the Protocone to the posterior 

 cusp, is another small cuspule placed somewhat nearer to the Protocone. On 

 the posterior slope of the main cone of the tooth is seen a minute cusp, distinct 

 from the posterior cingulum-cusp, which is, however, more marked in pm.-*. 

 A slight trace of the cingulum can be seen on the outer face of pm.*. 



The first molar has two external cusps of about equal size. Tiie cingulum 

 is seen anteriorly and posteriorly to these and also slightly on the external 

 face, especially of the anterior cusp (Paracone), where it becomes continuous 

 with the Protocone. The cusp situated between the Protocone and the posterior 

 part of the cingulum (seen in miniature in pm.'*) is well-marked. 



Internally to this again is a secondary cingulum, upon which is placed a 

 pronounced postero-lingual cusp, in front of which the .secondary cingulum 

 shelves downwards and forwards ; it then bifurcatt^s, one part running into 

 the Protocone, the other passing round in front of it to fuse with the primary 

 cingulum, externally to the Protocone. 



The second molar has similar characters to m.', but the Paracone is higher 

 and more pointed than the Metacone. 



The third molar is of the same pattern but is a smaller tooth, and therefore 

 the individual cusps are not so clearly differentiitei. 



Lower Jaw. — Incisors small and more procumbent than in the Dogs generally. 

 All are about equal in size. 



Ko diastema between i.'- and i.^. 



The third incisor has a well-marked internal r.inguliim rising into two small 

 cusps at its extremities, but from the position of the tooth they lie more 

 on the internal face than laterally. 



