[3.—CLASSIFICATION OF THE PRIMATES]

N.B.— * indicates extinct forms, + living groups, ++ the hypothetical stem-form. Cf. History of Creation, chap. xxvii.; Evolution of Man, chap. xxiii.

Orders.Sub-Orders.Families.Genera.
I
Prosimiae
Lemurs (Hemipitheci)

The orbits imperfectly separated from the temporal depression by a bony arch. Womb double or two-horned. Placenta diffuse, indeciduate (as a rule). Cerebrum relatively small, smooth, or little furrowed.

1. Lemuravida (Palalemures) Early lemurs (generalists)

Originally with claws on all or most fingers: later transition to nails. Tarsus primitive.

1. Pachylemures* (Hypopsodina)
Dent. 44 = 3.1.4.3/3.1.4.3
Primitive dentition
Archiprimas++
Lemuravus*
Early Eocene
Pelycodus*
Early Eocene
Hypopsodus*
Late Eocene
2. Necrolemures (Anaptomorpha
Dent. 40 = 2.1.4.3/2.1.4.3
Reduced dentition
Adapis*
Plesiadapis*
Necrolemur*
2. Lemurogona (Neolemures) Modern lemures (specialists)

All fingers usually have nails (except the second toe). Tarsus modified.

3. Autolemures+ (Lemurida)
Dent. 36 = 2.1.3.3/2.1.3.3
Specialised dentition
Eulemur
Hapalemur
Lepilemur
Nycticebus
Stenops
Galago
4. Chirolemures+ (Chiromyida) Dent. 18 = 1.0.1.3/1.0.0.3 Rodent dentitionChiromys
(Claws on all
fingers except first)
II
Simiae
Apes (Pitheci or simiales)

Orbits completely separated from the temporal depression by a bony septum. Womb simple, pear-shaped. Placenta discoid, deciduate. Cerebrum relatively large and much furrowed.

3. Platyrrhinae Flat-nosed apes Hesperopitheca Western apes (American). Nostrils lateral, with wide partition 3 premolars5. Arctopitheca+
Dent. 32 = 2.1.3.2/2.1.3.2
Nail on hallux only
Hapale
Midas
6. Dysmopitheca+
Dent. 36 = 2.1.3.3/2.1.3.3
Nails on all fingers
Callithrix
Nyctipithecus
Cebus
Mycetes
Ateles
4. Catarrhinae Narrow-nosed apes Eopitheca Eastern apes (Arctogoea) Europe, Asia, and Africa. Nostrils forward, with narrow septum 2 premolars. Nails on all fingers7. Cynopitheca+
Dent 32 = 2.1.2.3/2.1.2.3
Generally with tail and cheek-pouches. Sacrum with 3 or 4 vertebræ

Cynocephalus
Cercopithecus
Inuus
Semnopithecus
Colobus
Nasalis
8. Anthropomorpha+
Dent. 32 = 2.1.2.3/2.1.2.3
No tail or cheek-pouches Sacrum with 5 vertebræ

Hylobates
Satyrus
Pliopithecus*
Gorilla
Anthropithecus
Dryopithecus*
Pithecanthropus*
Homo

[4.—GENEALOGICAL TREE OF THE PRIMATES]

Anthropomorpha