NO. 2 A STUDY OF MENISCOTHERIUM — GAZIN 43 



conule is crescentic, paralleling the paracone, and its posterior limb 

 joins the inner wall of the paracone toward the center of the tooth. 

 There is, moreover, rather generally a highly variable complex of 

 plications extending from paracone, metacone, protoconule and meta- 

 conule into the median pit or valley of these two teeth. 



M 3 differs from the preceding molars in the narrower talon por- 

 tion, with the much less lingual position of the hypocone and the 

 shorter crest that this cusp forms with the metaconule. The lingual 

 portion of M 3 is surprisingly like that of P 4 - The development of 

 the external crests and styles, however, immediately distinguishes 

 these teeth. 



Lower dentition. — The lower incisors also appear comparatively 

 simple, although I have been unable to observe any in a completely 

 unworn state. They are much more procumbent than in the pre- 

 maxilla and exhibit longer and nearly straight roots. They are com- 

 paratively small with an anteroposteriorly compressed crown, and 

 I 2 , often the largest of the three, shows a more triangular wearing 

 surface. The root portion of the second incisor may also have 

 broader forward and somewhat more compressed (transversely) pos- 

 terodorsal portion. I 3 is larger than I t but may not always equal 

 I 2 in size and is rarely larger. Its wearing surface is oval in outline. 



The canine has a stronger root than the incisors and is closely 

 appressed to the third. Its crown, while tapering somewhat upward, 

 shows a high but relatively short anterior crest which wears much as 

 the third incisor. Its weak or subdued posterior crest is steeply 

 sloping and may exhibit an incipient cuspule or small buttress at its 

 base. 



Pi, single rooted, has a crown much like that of the canine, although 

 smaller and transversely more slender. P 2 may be single rooted or 

 double rooted, and in the latter instance the roots may not be com- 

 pletely divided. It is a little larger than P x , and its crown though 

 likewise simple is relatively lower and anteroposteriorly more elongate 

 with a longer anterior crest and usually a somewhat better defined 

 buttress at the base of the posterior crest. Very short diastemata 

 may separate this tooth in the series although occasionally Pi is the 

 isolated tooth, or still shorter diastemata may tend to isolate both. 



P 3 is double rooted and much larger than the preceding premolars. 

 The anterior crest, while somewhat variable in length and height, 

 always shows a marked medial flexure anteriorly, some specimens 

 exhibiting a distinct paraconid. The posterior crest is well defined, 



