1772 F. Siebenrock, 
Trionyx japoniciis 
Temm. et Schlag. 
Trionyx sinensis 
Wi egm. 
Trionyx schlegelii 
Brandt 
Carapace oval. 
Carapace short ovate 
in outline. 
Carapace short ovate. 
The anterior margin 
of the revolute nuchal 
border somewhatrugose 
with two small tuber- 
cles on the median Hne. 
The anterior margin 
of the revolute nuchal 
border segmented to- 
ward the median line, 
a Single tubercle on the 
latter in front of the 
border. 
Anterior border turn- 
ed Over backward, the 
outer (anterior) edge 
being smooth, the 
inner edge near the 
median line somewhat 
tuberculate with a cou- 
ple of rounded tuber- 
cles on top of the rim 
at the middle. 
Along the median 
line of the shell a raised 
keel anteriorly as broad 
as interorbital space 
and eyelids together, 
posteriorly not wider 
than this space plus 
half an eyeUd ; on each 
side of the keel a per- 
ceptible depression. 
No median keel, nor 
lateral depression, the 
carapace descending 
evenly to both sides 
from tc rounded back. 
With a broad, raised 
median keel and a well- 
marked depression on 
each side of the latter. 
Tlie skin of the cara- 
pace with numerous 
more or less disrupted, 
raised, longitudinal li- 
nes studded wiih tu- 
bercles, these lines be- 
ing more wavy and 
parallel with the axis 
of the body near the 
middle of the back, and 
straighter, less tubercles 
gather into a large 
Cluster on the nuchal 
portion of the keel, and 
a still greater number 
oflarger tubercles con- 
gregate near the pos- 
Skin of carapace 
smooth, with about 24 
longitudinal raised 
lines, which are enti- 
rely untubexulated, 
and nearly all straight 
and uninterrupted, ex- 
cept about three mid- 
way on each side, 
Vv'hich are wavy and 
occasionally interrupt- 
ed; these lines termi- 
nate near the posterior 
end of the bony disk in 
a small tubercle behind 
which to the end of the 
carapace there are nu- 
Carapace with nu- 
merous strongly tuber- 
culated longitudinal 
lines, the outer ones 
more orless continuous 
and parallel with the 
outer edge, the inner 
ones very irregulär and 
interrupted; posterior 
enJ densely tubercu- 
lated as is also the 
nuchal region. 
