4;)8 \\ . K. grp:gory — notharctds and lemueoidea 



Lower canines inoi'o (Microcliceriis) or less {Nerroleinur) enlarged. 



Vn\., small. 



Pm* bi- or tri(U!S})id, with high external cusp, two internal cusps, and 



heavy iiiteinal cinguhim. 

 M', M- (|iiailrilalci'al witli foiii- niaiji c-usps, large |(rolo- ;uul inelacouules, 



and an acee.ssorv eonnic between Ihc protoeonc and the nietaconule ; 



mesostyle present or absent. 

 M^ much smaller than m-, with oblique ectoloph. 

 Lower molars m., m^ with paraconid. absent. 

 Mastoids mucb inflated; mastoid inflation demarcated from bulla l)y a 



constriction. (Mastoid sinus perhaps less widely opening into 



bulla.) 

 Genera: MicrucJiwru.^. Necrolemur. 



Family Tarsiidse 



Lower, Middle, and I'pper Eocene, N^orth America: h'ecent, East Indies. 



Dental formula : 1 1-^, C-' P^^> M-- 



2-0(?) 1 3-2 3 



Anterior pair of upper incisors in contact, enlarged, with vertically ex- 

 tended crowns [l^arsius). 



Lateral upper incisors ininute, posteroexternal to mediaji pair. 



Lower incisors, Aarying in size, with crowns more erect tlian in Lorisida': 

 one or Ijoth ])airs sometimes wanting.'^ 



Upper canines varying in size, wholly posterior to incisors. 



Lower canines sometimes enlarged, vertical or semi-procumbent. 



Pni2 small or absent : pm^ lncu,spid. 



Pm^ minute to absent ; pnr', jun^ bicuspid. 



M^, ]\I- tritubercular, with small proto- and meiaconules; mesostyle 

 rarely present : hypocone small to al^sent. 



M^ tritubercular. 



Lower molars tuberculo-sectorial, witli small, Jiigli (rigonid and low 

 talonid. Paraconid present ty])ically well developed. 



Mastoids not or but little inflated: occijnit well rounded. 



Placenta discoidal, deciduous (Tardus). 



Genera: Tetonius, SJioshonius, Anapfomorpliits, Lower Eocene; Oino- 

 mys, Hemiacodon, Washahiufi, Middle Eocene; Uinfanius, Upper 

 Eocene ; Tarsius, Recent. 



' In certain Lower Eocene forms recently described by Doctor Matthew, op. cit. 



