The skin was dense, and its impression is preserved in most specimens, as may be seen in the subjoined and following figures.

Enlarged three times. Dorsal view.

When highly magnified, slight ridges are seen upon it; these are the first indications of scales, which become more developed on

FIG. 3.-Upper side. Restoration of the skull of Branchiosaurus salamandroides, Fritsch. Enlarged six times.

the under-side of the body. The scales are ovate, truncated in front and somewhat irregular behind.

In the median part of the abdomen the scales are long, and assume

a V pattern. The impressions of small rounded bodies seen in this region upon the scales are considered to be eggs.

The form of the skull and general relations of the bones will best be gathered from Figs. 3 and 4. The osteological details are given by the author at great length. The premaxillaries (im) are ornamented with delicate long pits, and carry from 6 to 10 short pointed teeth, which are larger than those in the maxillary bones and lower jaw; they are smooth and have a round pulp-cavity.

Six times natural size.

The

The maxillary (MS.), which is similarly pitted, and extends back to the quadrato-jugal (QJ.), carries from 10 to 18 teeth. There are probably two or three irregular rows of teeth behind these. The nasal bones (N.) are notched in front to form with the premaxillary bones the small nasal apertures, which they border on the inner side with an elevated ridge. The lachrymal bone is absent. frontal bone (F.) is excluded from the circle of the orbit by the triangular prefrontal bone (P.) in front, and the sickle-shaped postfrontal bone (Pt. f.) behind. Its upper surface is covered with delicate long pits; and the post-frontal bone is strongly sculptured. The triangular post-orbital bone (Pt. o.) forms the outer and hinder border of the orbit. The jugal (Ju.) is a long bone which extends back from the nasal and parallel to the maxillary, so as to form part of the border of the orbit, and partly divide the quadrato-jugal (QJ.) from the supratemporal (S.T.). Between the parietal bones (Pa.) in the middle of the suture is the ovate or round foramen parietale,

measuring a fifth or a sixth of the length of the suture. The Epiotic (Ep.) terminates backward and outward in a strong free process; it bounds the ear. In the outer edge of the supra-temporal bone (S.T) is often a notch, which may indicate the outer opening of the ear. The quadrate bone (Q.) is very small. The supra-occipital (S.O.) is well developed; but the exoccipitals cannot be determined with certainty, though they may form the occipital condyles. The under-side of the skull, Fig. 4, is remarkable for the large size of the palatal apertures, which are defined by the parasphenoid bone (Ps.) in the middle, by the pterygoids (Pt.) at the outer sides, and by the palatine bones (p) in front. As in some living Urodela, there is a small aperture in the sutural line between the vomers (V.). There are traces of small groups of teeth on the hinder and outer edges of the vomerine bones.

The lower jaw always becomes attenuated anteriorly. It consists of three bones, articular, angular, and dentary. The latter element carries a row of about 20 large smooth teeth.

The sclerotic circle is made up of about 14 oblong plates, which are marked with concentric lines.

On each side of the hinder part of the skull are two branchial arches which carry two rows of strong spheroidal bones, each bearing a little curved spine.

The vertebral column is divided into back and tail. From the head to the pelvis there are about 20 vertebræ, and all except the first bear ribs. The second to the thirteenth are all about the same size. All are compressed to the thinness of paper, so that the details of their structure are obscure. Lower down the back the vertebræ

slightly decrease in size. There is apparently only one sacral vertebra, which is always covered by the pelvic bones. There are about 21 vertebræ in the tail, gradually diminishing in size to a fourth of their original width.

The dorsal ribs from 2nd to 13th have a length equal to threequarters of the width of a vertebra; posterior to this they become shortened. Ribs exist in the tail, and are about half as long as the vertebræ are wide.

The shoulder girdle includes seven bones, scapula, coracoids, clavicles and thoracic scute; and the pelvic girdle is formed by the iliac and ischiopubic bones. The hind-foot has the digits much longer than in the fore-foot, but the longest digit is the second, while in the fore-limb the third digit is longest. In the fore-limb the number of the phalanges is 2, 2, 3, 3, 2, and in the hind-limb it is 3, 4, 3, 2, 2.

The other species of Branchiosaurus which are described and figured are B. umbrosus, Frit., B. Moravicus, Frit., previously described as Archegosaurus austriacus of Makovsky, B.? venosus, Frit., and B.? robustus, Frit.

The next genus, Sparodus, Fritsch, is represented by two species: S. validus, Fr., and S. crassidens, Fr. It is nearly related to the American genus Hylerpeton and to Brachiderpeton. The large broad vomer carries numerous uneven large conical teeth. And the palatine bone has a single row of teeth, which increase in size posteriorly.

In Sparodus validus there are 17 teeth in the lower jaw; and there are 27 on each vomer, the largest rows being towards the palatine bone. The palatine bone carries 11 teeth. The skull is more wedgeshaped than in Branchiosaurus.

Of Hylonomus two species are recognized, but these are only known from small portions of jaws. Hylonomus acuminatus has the teeth marked with distant parallel ribs.

The last genus in the present part of the work is named Dawsonia. It is very nearly allied to Hylonomus, but the author is unable to see his way to uniting the genera, because Dr. Dawson figures elements of the skeleton which differ from the Bohemian specimens. The vomer (v) has a small group of minute teeth on its outer edge,

FIG. 5.-Restoration of the under-side of the skull of Dawsonia polydens, Fritsch. Twice the natural size.

and both the parasphenoid (Pf.) and pterygoid (Pt.) carry numerous small teeth. The palatine bone (p) has a single row of teeth which become larger posteriorly. The hindermost and largest tooth is grooved at the base. The external surface of the skull-bones is strongly sculptured. The thoracic scute has a long rhomboidal form, and is furrowed like the skull-bones. The teeth in the jaws are smooth and of uniform size. The premaxillary is broad, with about eight large teeth of equal size. The anterior process of the parasphenoid widens in front, and is slightly forked. This skull has never yet been found entire, but has been reconstructed from several fragments, and is believed to have been rather broader than long. The vomer (v) is forked behind, as though for the posterior nares.

The