6 42 
DR. J. W. DAWSON GIST ERECT TREES CONTAINING ANIMAL 
I have dedicated the genus to Professor Anton Fritsch, who has so ably illustrated 
the carboniferous and permian Batrachians of Bohemia. 
Bones of the head very smooth, having only a few microscopic punctures. Teeth 
conical, somewhat obtuse, striated at the inner side of the apices ; there are about 
thirty in each ramus of the mandible, and about twenty-seven in the maxillary bone. 
As in the other Microsauria, they are implanted in a furrow. 
Vertebrae short and well ossified, three in a centimetre. Bibs strong, curved, about 
1 centimetre in length. 
Limbs robust, the bones better ossified than in any of the other species of Micro¬ 
sauria. Humerus round, and with a distinct keel on the shaft. Femur with well- 
formed articulating surfaces. Toes of hind foot probably five, central ones long and 
slender. 
Thoracic plate of moderate size and somewhat rounded. Abdomen protected by 
needle-like rods, which are very numerous, and were probably arranged en chevron. 
Length of mandible (not quite perfect) . . 2T centimetres. 
„ maxilla.2 „ 
„ rib.1 
,, humerus. 2 
,, femur.2 "4 
,, radius and tibia .... about 1 „ 
„ toe of hind foot.7 millimetres. 
Eight teeth in 5 millimetres. 
Under the microscope the bone shows small rounded cells with numerous canaliculi. 
The cells in the limb bones are a little longer than the others. The teeth are simple, 
and consist of dentine traversed by moderately fine and somewhat tortuous tubes ; 
these are much coarser than in Hylonomus , but finer than in Hylerpeton. 
9. Dendrerpeton Acadianum , Owen (Plate 40, figs. 46 to 51; and Plate 44, figs. 129 
to 137, except fig. 131). 
[Owen, Journal of Geological Society, vol. ix. Dawson, c Air-breathers of the Coal 
Period,’ p. 17 ; ‘Acadian Geology,’ p. 362.] 
Portions of several specimens of this species are in the new material, but do not add 
much to the knowledge of its characters, which have been fully given by Owen from 
the somewhat complete specimens obtained by me in 1859. 
Some interesting fragments of cuticle were found in association with one of the 
skeletons, which show very well the scaly covering of the back and the lappets and 
edge-scales of the sides. These last probably formed a border or margin to the bony 
scales covering the abdomen (Plate 40, figs. 46 to 51). 
