12 Frederick CJtapman : 



column is well-marked by a deep, interrupted groove. The sutures 

 •of the costal plates are faintly visible. The impressions of the 

 bones of the pelvic girdle are also seen. On the ventral side 

 impressions of the bones of the plastron may be made out, and also 

 those of the epidermal plates; of the latter the most strongly 

 marked are the grooves between the pectoral and abdominal 

 shields. 



This fossil cast is referable to the genus Emydura, Bonaparte, ^ 

 to which the Murray Mud-tortoise belongs. From all appearances 

 the fossil may be referred, with some reservation, to the same 

 species, Emydura niacquariae, Gray sp.2 



The length of the fossil specimen when complete was about 28 

 cm., as against 27 cm. of a full-grown living specimen. 5 Breadth, 

 about 15 cm. A living example from Wahgunyah, mentioned by 

 McCoy, shows almost identical proportions. This fossil is slightly 

 broaden in proportion, both across the carapace and plastron, than 

 the living specimens, but this difference seems to be due to com- 

 pression. 



Observations. — The Murray Mud-tortoise is common in the 

 River Murraj^ and its tributaries and branches, but is not found in 

 Victoria in rivers flowing to the south. This curious point in its 

 local distribution may indicate the once northern trend of the 

 rivers in the Casterton district, which now join the Glenelg. 



Anent the discovery of the specimen, the question arises whether 

 this ironstone deposit bears any relationship to that occurring at 

 Hedruth, which yielded Eiicah/pfus and Banksia leaves, and a 

 'bird's feather.'' Carapook is in the same district as Redruth, and 



1. Arch. f. Naturgeschichte, 1S38, Vol. I., p. 140. 

 ;2. Hydrasiiis macquarii, Gray, 1831, Syd. Rept., p. 40. 



Platemys macquariae, Gray sp., Dumeril and Bibron, Erp. Gen., Vol. II., 



p. 438. 

 Hydraspis victoriae, Gray 1842, Zool. Misc., p. 55. 

 Chelymys macquaria (pars). Gray, 1844, Cat. Tort, p. 42 . 

 Euchelymys sulcifera, Gray, 1871. Ann. Mag. Nat. Hist. ser. 4, Vol. 



VIII., p. lis. 

 Euchelymys sulcifera, Gray, 1872, Proc. Zool. Soc. Lond., p. 508. 

 Chelymys victoi-iae (pars). Gray, Proc. Zool. Soc. Lond., p. 506, pi. 



XXVII. 

 Chelymys macquaria, Cuvier sp. McCoy,, 1884, Prod. Zool. Vict. pp. 11-14, 



pi LXXXII. and LXXXIII. 

 Emydura macquariae. Gray sp. Boulenger, 1889, Cat. Chelonians, 



Rhynchocephalians and Crocodiles in the Brit. Mus., p. 230, 



Pig. 63. 

 Emydura macqxiariae, L,ydekker, 1889, Cat. Poss, Rept. and Amphibia. 



Brit. Mus., p. 169. 

 ■Z. Prod. Zool. Vict., Vol. I., 1884, p. 12. 



-4. See Proc. Roy. Soc. Vict., Vol. XXIII. (N.S.), pt. I.. 1910. pp. 23-26, pis. 

 IV., V. 



