554 
PROFESSOR OWEN OFT SOME REMAINS OF THE 
complex defensive peripheral developments of the osseous tail-armour of Glyptodcm 
clavipes. But the species of Glyptodon of which the tail-sheath more closely resembles 
that of Megalania, as exemplified by the subjects of the present paper, is the Glyptodon 
(Schistopleurum ) asper of Burmeister.* 
The bony tail-rings are nine in number (Plate 66, fig. S), and each ring is composed, 
as in Glyptodon clavipes, and, partially, in Uromastix princeps, of a smaller and larger 
series of ossicles (ib., d, e ); but those of the hinder series (e) are each developed into a 
conical protuberance, smallest in the two proximal rings and increasing in size, 
prominence, and sharpness of apex, to the fourth ring; thence the horn-like bosses 
decrease in number, though hardly in size, to the terminal closed segment of the 
sheath. 
In an antecedent girdle may be distinguished one dorsal pair (Plate 65, fig. 5, a, a), 
a dorso-lateral pair (ib., b, b), a ventro-lateral pair (ib., c, c), and two smaller ventral 
pairs (cl, d'), of massive conical protuberances. 
In number and arrangement the pattern of the small existing Lacertian (Moloch) is 
adhered to ; but the great Armadillo, in the osseous basis of the protuberances as well 
as in their relative size, repeats more closely the armature of the terminal segments of 
the bony tail-sheath of Megalania, The relations of the exo- to the endo-skeleton are 
also essentially the same. The neural spine of the caudal vetebra, in Glyptodon, rises 
to contact with the roof of the overarching bone, but expands and divides to give a 
more extended support (ib., ib.). The haemal spine in like manner expands, but in a 
minor degree, upon the floor of the cylinder. Moreover, in the caudal segment, the 
subject of fig. 5, the transverse processes are developed and similarly expand to buttress 
the side walls of the dermosteal sheath. 
In the caudal segment of Megalania, the subject of Plate 64, both neural and 
hsemal spines do expand at their terminal confluence with the sheath, and if, as is 
probable, the lack of extension of the transverse processes (cl, cl) be due to accidental 
fracture and loss, the inward projections o£ the parts of the sheath against which, if 
entire, they abutted, indicate, also, expanded terminations. But the difference in the 
relative size of the endoskeletal element of the tail-segment is manifestly in favour 
of the Mammal. 
The unlooked for anticipation, so to speak, of the loricate character of tail of certain 
members of placental Mammals by a genus of oviparous Lacertians has suggested the 
following final remarks. 
The Pangolins (Manis) offer a singular exception in their high class to other 
Mammalia in the scaly nature of their tegument in which the imbricate arrangement 
of the horny tissue repeats the common condition of the covering of Lizards. I 
conceive this, with their toothless character, their gizzard and gastric glands, and 
then’ Reptilian retention of intra-abdominal testes, to contribute a more significant 
indication of their position in the scale of the warm-blooded, viviparous, and lactiferous 
* ‘ Anales del Museo Publico de Buenos Ayres,’ 4to., 1871, p. 411, plate 40. 
