ON THE CLASSIFICATION OF THE LABYRINTHODONTS. 149 
Report of the Committee, consisting of Professor Huxiry, LL.D., 
F.R.S., Professor Harkness, F.R.S., Henry Woopwarp, F.R.S., 
James Tuomson, JoHn Brice, and L. C. Matt, on the Structure 
and Classification of the Labyrinthodonts. Drawn up by L. C. 
Mia, Secretary to the Committee. 
(PuatEs IV.-VII.) 
In this, as in the preceding Report, the Committee have included the Permian 
and Secondary Labyrinthodonts. Before their work had made much pro- 
gress it was perceived that the Carboniferous species cannot be satisfactorily 
studied alone. 
The present Report treats of all the well-investigated species hitherto 
recorded, and the Committee have not, therefore, recommended their own 
reappointment. In laying down their commission, they desire to thank the 
many friends who have assisted their labours. Professor Cope, Messrs. 
Embleton and Atthey, Mr. T. P. Barkas, and the Natural-History Society of 
Northumberland and Durham have forwarded publications on Labyrintho- 
donts ; the authorities of the Warwick and Bristol Museums, Mr. John Ward 
of Longton, Mr. James Thomson of Glasgow, Mr. George Maw of Broseley, 
Mr. T. P. Barkas of Newcastle, and Mr. William Horne of Leyburn, Wens- 
leydale, have sent specimens for examination ; while Professor Cope and Mr. 
Thomson haye sent photographs from fossils in their possession. Every 
facility for examination of Labyrinthodont remains has been afforded by 
the officers of the various public museums visited; and two members of 
the Committee have had the advantage of inspecting a‘large part of the 
valuable collection belonging to Mr, Thomas Atthey, of Gosforth, near New- 
castle. 
It does not appear necessary to prefix to the arrangement of the Laby- 
rinthodonts here proposed any discussion of the opinions of previous writers 
on this subject. In no classification that has yet appeared have evéh one 
fourth of the genera here recorded been noticed at all. We are sensible of 
the great imperfection of the materials at our command, and can only regard 
the present arrangement as a sketch to be filled in and corrected hereafter. 
CHARACTERS OF THE ORDER. 
Body elongate, furnished with a tail. Postorbital, supratemporal, epiotic, 
and paired supraoccipital ossifications usually present in the skull. A _ parietal 
foramen. Palatine and vomerine teeth in most or all. Dentine usually much 
folded’; the apex of the young tooth two-edged. A sclerotic orbital ring in 
some, possibly in all. Vertebrae amphiccelous. Three. thoracic plates’, and a 
ventral armour of small scutes. Limbs four’, often, perhaps usually, pentadactyle. 
TABULAR VIEW OF THE CLASSIFICATION OF THE 
LABYRINTHODONTA. 
A. Centra of dorsal vertebre discoidal*.—Genera 1 to 23. 
I. Evetypra. Cranial bones strongly sculptured. Lyra conspicuous. Mandible 
1 Slightly folded at the base only in some of the teeth of Dendrerpeton; simple in 
Hylonomus and Hylerpeton. 
* Unknown in the Microsauria, as well as in various genera and species which have 
been hitherto represented only by fragmentary examples. 
8 Believed to be wanting in Ophiderpeton and Dolichosoma. 
4 This character is not of primary importance, but seems to be available for an arrange- 
ment determined by other considerations. 
