346. On the Evolution of the Vertebrata, [April, 
give a clearly cut analysis, especially from the skeleton alone. 
The following scheme, therefore, while it expresses the natural 
groupings and affinities, is defective in that some of the defini- 
tions are not without exceptions : 
I. A large coracoid bone articulating with the sternum. 
Marsupial bones; fibula articulating with proximal end of astragalus - 
. Monotremata, 
II. Coracoid a small process codssified with the scapula. 
a, Marsupial bones; palate with perforations (vagina double ; placenta and 
corpus callosum rudimental or wanting ; cerebral hemispheres small 
and smooth 
But one ine molar tooth 2. Marsupialia. 
aa, No marsupial bones; palate entire (one vagina; placenta and corpus 
Calbia well dev es ed). 
f. Anterior limb reduced to more or less inflexible paddles, posterior 
limbs wanting (Mutilata), ` 
No elbow joint; carpals discoid, and with the digits separated by cartilage; lower 
jaw without asce nding ramus -o o 3e Cetacea. 
An elbow joint; wa and phalanges with normal aiticdlations - : bwer jaw with 
ascending ram 4. Sirenia. 
8: pase limbs with flexible joints and distinct digits; ungual pha- 
langes not compressed, and acute at apex! (Ungulata’). 
Y» Tarsal bones in linear series; carpals generally in linear series. 
Limbs ideal ; teeth with enamel 5. Taxeopoda! 
yy. T arsal series alternating ; carpal series linear. 
series linear; no intermedium ; fibula not interlocking with astragalus ; no 
anapophyses ; incisors rooted; hallux not opposable.,........... Condylartha. 
Carpal series ene an intermedium ; fibula interlocking with astragalus ; hallux not 
opposabl yracoidea. 
An interdiėdtan, menir not interlocking; anapophyses; hallux opposable ; aE 
growing from persistent pulps 
An panepen fibula a acne: anapophyses; hallux opposable; incisors 
; carpus generally linear..... Quadrumana. 
No Sea ay: nor anapophyses ; LA rows alternating ; incisors rooted 
Anthropoidea. 
The only difference between the Taxeopoda and the Bunotheria is in the unguli- 
form terminal phalanges of the former as compared with the clawed or unguiculate 
form in the latter, oe marmosets among the former division are, however, fur- 
nished with typical : 
me may prefer ot use the term Primates in place of Taxeopoda, and such may 
be the better course. 
Cuboid bone partly supporting navicular, not in contact with astragalu 
‘a Proboscidia. 
Pe ae 
1Except the Hapalide. 
* Lamarck, Zoologie Philosophique, 1809. 
| 3 This order has the following suborders, whose association is now made for the 
first time. 
— in Pithecus and Hylobates. 
