Mr. J. Miers on the Menispermacee. 97 
fifth, and the second placing the thumb in the place of the fifth 
toe, calculating that the animal most resembled Dasypus, which 
has five toes on the hand, and not Praopus, which possesses only 
four. But the construction of the armour, especially of its horny 
covering, demonstrates that the Gl, yptodon was more similar in 
its constr uction to Praopus than to Dasypus. . 
The leg is very strong: undoubtedly the femur is the strongest 
of all the bones of the skeleton. At its head there is no cavity 
for the ligamentum teres, and from the outer side of the head arises 
avery prominent trochanter major. We also see a corresponding 
prolongation on the outer side of the external inferior condyle. 
The tibia and the fibula are united into one bone largely per- 
forated in the middle ; and the foot is very thick, high, and short, 
with a calcaneum rather prominent posteriorly, which proves 
that the animal was plantigrade, like the Armadillos. The bones 
of the tarsus are complete; but those of the fore part are very 
short, like the metacarpals of the five toes. These have the 
general configuration of those in unguiculated animals, as the 
ungual bones are very broad and strong. 
We shall finally conclude this description with the notice of 
the fact that in the hand as well as in the foot there are peculiar 
bones, which are the sesamoid bones. There are three similar 
bones in the hand for the three toes next the thumb, which are 
developed below the phalanges beyond the ungual bone. But 
in the foot there are ten sesamoid bones, one in each toe, ex- 
cepting the “hallux,’ and below the second anterior ungual 
phalanx, and two on the inferior part of the metatarsal bones of 
the three median digits. These last have a very peculiar form, 
as they are divaricated, to permit the principal digital tendons 
to pass through them. There is another bone of a very peculiar 
form in the centre of the hand, to which the tendons of the toes 
are attached. A similar bone also exists in some existing Ar- 
madillos, and is described by Cuvier in his work ‘ Recherches sur 
les Ossemens Fossiles,’ tom. v. p. 128, tab. 2. figs 12 & 13. 
X.—On the Menispermacez. 
By Joun Miers, F.R.S., F.L.S. &c. 
[Continued from p. 53. | 
12. OponTocaRYA. 
Tuis is the only South-American form, as Calycocarpum is the 
sole North-American genus, of the Heterocliniee hitherto known, 
all the other eleven genera of this tribe belonging to Asia or 
Africa. The plant on which this genus was established was 
found by me in the Organ Mountains as far back as 1828, and 
Ann. & Mag. N. Hist. Ser.3. Vol. xiv. 7 
