72 Amphibia Microsauria, Aistopoda, and Branchiosauria. 



Wall-case, 

 No. 11. 



Table-case, 

 No. 22. 



SUB-ORDER 1. Mierosauria. 



This sub-order contains a number of salamander-like forms 

 of Labyrinthodonts referred to the family Urocordylidce, and to 

 the genera Urocordylus, Ceraterpetum, Lepterpetum, from Kil- 

 kenny, Ireland, and from Bohemia. Limnerpetum, from 

 Bohemia, occupies a family by itself. The Hy lonomidce include 

 Hylonomus, Seeleya, Ricnodon, Orthopleurosaurus, all from the 

 Gas-coal of Bohemia. Microbrachis, also from Nyran, Bohemia, 

 occupies a distinct family. Most of these are represented by 

 electrotypes of the original fossils, the shales in which they 

 occur as fossils being charged with pyrites, which rapidly 

 decompose. 



Wall-case, 

 No. 11. 



Table-case, 

 No. 22. 



SUB-ORDER 2. Aistopoda. 



In this sub-order the body is snake-like without legs, and 

 there is neither a pectoral nor pelvic girdle ; the centra of the 

 vertebrae are elongated, and the neural spines aborted. It 

 includes Dolichosoma and Ophiderpetum (Huxley) from the coal 

 of Ireland and the Permian of Bohemia. 



Table-case, 

 No, 22. 



Wall-case, 

 No. 11. 



SUB-ORDER 3. Branchiosauria. 



These are short-tailed salamander-like Labyrinthodonts 

 with barrel-shaped centra, and a notochordal canal through 

 their vertebrae. 



The family APATEONID^ includes Melanerpetum from Bohemia ; 

 and the family PROTRITONID.E the genera Protriton of Gaudry, 

 from the Lower Permian of Autun, and Bohemia, Sparodus and 

 Dawsonia also from the last-named locality. 



Among doubtful Labyrinthodonts may be recorded here, 

 Lepidotosaurus Duffii from the Middle Permian of Midderidge, 

 Durham. Some of the Ichnites (Footprints) were doubtless 

 made by Amphibians ; they are mentioned under that head in 

 Gallery No. 11 (see infra, p. 73 of this Guide, Fig. 95). 



FOOTPRINTS. GALLERY No. 11. 



Footprints. 



Wall-cases Nos. 8-10 are occupied by a fine series of Foot- 

 prints and impressions mostly found in Sandstone of Triassic 

 age. Attention is directed to the large slab from near Greenfield, 

 Massachusetts, which is covered with impressions supposed to 

 be the footmarks of bipedal reptiles ; these tracks are called 

 "Ichnites." 



