ANOMODONTS. 
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vertebrae are slightly cupped at each end throughout the series, and intercentra 
are present. 
The Anomodonts, or Mammal-Like Reptiles. 
Order Anomodontia. 
The last order of Reptiles, which is entirely extinct and confined to the 
Triassic and Permian epochs, is of especial interest to the evolutionist as being 
nearly allied to the ancestral stock from which Mammals have originated, and also 
equally closely related to certain extinct Amphibians noticed in the sequel, which 
were themselves evidently not far removed from the type whence sprang both 
Reptiles and Mammals. It should be observed, however, that these Anomodonts 
show the nearest relationship to the Egg-laying Mammals, and until we know the 
true affinity of 
the latter to the 
other members 
of the same class, 
it is of course 
impossible to at¬ 
tempt to define 
the genealogy 
more exactly. 
The Anomodonts 
are the only 
reptiles which 
agree with the 
Egg - laying 
Mammals in 
having three dis¬ 
tinct bones on THE eight side of the pelvis (A) AND shoulder-girdle (B) of an anomodont. 
each side of the il, haunch-bone, or ilium ; is, ischium ; pb, pubis ; of, foramen between ischium and 
true shoulder- P ul ^ s > sc > blade-bone, or scapula ; p.cor, coracoid ; cor, metacoracoid ; gl, cavity for head 
of upper arm-bone, or humerus. 
girdle; that is 
to say, a blade-bone, or scapula, above, and a coracoid and metacoracoid below. 
Then the pelvis is very mammal-like, not only in that its three elements are 
united, but likewise in the small size of the vacuity, or foramen (of) between 
the pubis and ischium. It will also be seen from the two figures here given how 
close is the resemblance between the pelvis and shoulder-girdle of these reptiles, 
each having one bone above and two below. Even still more marked is the 
similarity between the upper arm-bone or humerus of the Anomodonts and that 
of the Egg-laying Mammals; each having a perforation on the inner border of 
the lower end, whereas in those existing reptiles which possess such a perfora¬ 
tion (with the exception of the tuatera, where there is one on each side), it is 
situated on the outer border. As a rule, the Anomodonts further resemble 
Mammals in the absence of abdominal ribs; and there are important similarities 
in the structure of the skull. 
