GIGANTIC LAND-LIZARD FROM AUSTRALIA. 
1049 
Addendum. 
(Added October 15, 1880.) 
From the subjects of Part I. (1858) the inference was that a Land-Lizard of unusual 
size had existed in Australia; suggesting farther quest of such character among 
existing Lizards, with the result that the largest known species was Australian. 
Any doubt that lingered was as to the validity of separating generically Megcdania 
from Hydrosaurus. It was possible that the discovery of the fossil skull might 
require a generic synonymy with the existing carnivorous sj)ecies ; and it seemed very 
probable that, in habits, the extinct might agree with the large existing Lizard. 
As years elapsed with successive acquisitions of other parts of the great extinct 
Lizard, and especially the reception, in 1866, of the occipital vertebra, these fossils 
led to the detection of such differences in the corresponding parts of Hydrosaurus 
giganteus as to confirm the original inference of generic distinction. But other 
portions of the skull were wanting to deal profitably with this advance of insight. 
Accordingly, my instructions and desires were pressed importunately on friendly 
collectors and transmitters of Australian fossils; and, in 1879, met with the return 
which has enabled the above contribution of Part II. 
Description of the Plates. 
PLATE 34. 
Fig. 1. Side view of a dorsal vertebra. Megcdania jorisca. 
Fig. 2. Front view of the same. Ib. 
Fig. 3. Side view of a dorsal vertebra. Moloch horrid,us. 
Fig. 4. Front view of the same. Ib. 
All the figures are of the natural size. 
PLATE 35. 
Fig. 1. Back view of a sacral vertebra. Magadan ict pulsed. 
.Fig. 2. Under view of the same. Ib. 
Fig. 3. Front view of a caudal vertebra. Megcdania prisca. 
Fig. 4. Side view of the same. Ib. 
Fig. 5. Front view of a sacral vertebra. Moloch horridus. 
Fig. 6. Side view of a caudal vertebra with the haemal spine. Ib. 
All the figures are of the natural size. 
6 T 
MDCCCLXXX. 
