132 DR. J. E. GRAY ON THE CHELYDID#. [Mar. 8, 
erect bony folds in front. Crown of head with numerous polygonal 
tesseree. Skull solid. Chin not bearded. Legs with small scales. 
Hab. Australia. 
* Nuchal shield broad and well developed ; hinder margin of shell 
entire. 
1. CHeLymys macauartiA, Gray, J. c. 57; Ann. & Mag. N. H. 
1863, xii. 98. (Head, fig. 3.) 
Fig. 3. 
Chelymys macquaria. 
** Nuchal shield none ; hinder margin of the young shell dentated ; 
vertebral plate nodulose. 
2. CueLyMys DeNTATA, Gray, Ann. & Mag. N.H.ser.3. xii. p. 98. 
C. elseyi, Gray. 
Hab. North Australia (Mr. Elsey). 
B. Head covered with hard, symmetrical horny plates. The skull 
with a largely developed zygomatic arch, which is often dilated 
posteriorly, so as to cover the upper hinder part of the temporal 
muscle with a bony case. Lower jaw strong. Beak naked. 
Nuchal and gular plate marginal. , 
a. Head depressed, witha deep longitudinal frontal groove. The 
skull depressed. Zygomatic arch moderately developed. Tem- 
poral muscles covered with hard dermal shields. Alveolar sur- 
Jace of the jaws thin, with a small submarginal ridge. Claws 
5—5. Africa. Emydoid Chelydide. 
7. SrERNOTHERUS, Gray, Cat. Shield Rept. 51; P.Z.S.1863,p.192. 
Front lobe of sternum mobile, with an internal process on each 
side. 
Hab. Africa and Madagascar. 
* Crown-shield on a line with the back of the tympanum. 'Tanoa. 
1. STERNOTH#RUS sINvATUs, Gray, P. Z. 8.1863, p. 193 (figure 
of head). 
