62 
Amphib ia — E ca udata. 
Amphibia. 
Gallery, 
No. 4. 
Table-cases, 
Nos. 23 and 
24. 
West Cor- 
ridor, 
No. 5. 
Wall-case, 
No. 11. 
Table-case, 
No. 24. 
Batrachia ; 
Frogs, 
Toads. 
Class 4.— AMPHIBIA. 
In Wall-case Ho. 11, and in Table-cases Nos. 23 and 24, are 
placed the fossil Amphibia or Batrachia (Frogs, Toads, Newts, 
and Salamanders). These animals are distinguished from true 
reptiles by the fact that the young undergo certain metamor- 
phoses after leaving the egg. In this stage of their existence 
they breathe by external gills : these gills are occasionally 
retained along with internal lungs in the adult animal. The 
limbs are sometimes all absent, or one pair may be wanting. 
When present, they have the same bones as in the higher 
animals ; they are never converted into fins. The skull has two 
occipital condyles and a persistently cartilaginous basi- and 
supra-occipital. The suspensorial apparatus of the mandible 
is continuous with the skull. Teeth are commonly present on 
the premaxilla, maxilla, vomer, and the dentary bone of the 
mandible. They are usually anchylosed to the bone and are 
simple in structure ; but in the Labyrinthodonts they are more 
complex. There are never more than two vertebrae coalesced 
to form the sacrum. The tail is comparatively short. The 
centrum of the backbone is sometimes found to be unossified, 
forming a mere ring of bone, the interior being gelatinous. 
This form of backbone is called “Notochordal,” and is cha- 
racteristic of the oldest reptilia belonging to this group met 
with fossil in the Coal Measures, such as the Anthracosaurus, 
Archcegosaurus, and the Triassic Labyrinthodonts. 
Order I. — ECAUDATA. (Tailless Batrachia, Frogs and 
Toads.) 
The body of adult is short, destitute of a tail, and furnished 
with four limbs, of which the pelvic pair are the larger and 
adapted for leaping. There are no gills in the adult. Skull 
short and wide, with the parietals confluent with the frontals, 
and the orbits usually undefined ; prsesacral vertebrae few in 
number, and generally proccelous ; there is only one sacral 
vertebra, and the vertebral column terminates in a longurostvle ; 
dorsal ribs are usually absent. Ilia prolonged backwards, so as 
to throw the acetabulum far behind the sacrum ; radius and ulna, 
and tibia and fibula respectively fused together, calcaneum and 
astragalus elongated : Four digits in the hand and five in the 
foot ; an additional ossicle in the pes may represent the preliallux. 
The tailless Batrachia (frogs and toads) do not date back 
further in time than the Upper Eocene. 
The European genus Bombinator is probably represented in 
the Upper Miocene of Switzerland and the Middle Miocene of 
Sansan, France. Another genus Bvfavus, occurs in the Middle 
Tertiary of Italy. Felobates is found in the Miocene of Sansan, 
