170 R. ETHERIDGE, T. W. E. DAVID, AND J. W. GREMSHAW. 
mark, the roots descending three feet. It was situated as near 
as possible in the middle of the canal, 2,100 feet north of Rickety 
Street Bridge. The roots rested on six inches of loamy sand. 
passing down into a grey unctuous. clay. This stump belongs to, 
the Mahogany, Lucalyptus sp. 
No. 6 Stump was also apparently in sitw, its top being six feet 
eight inches, and the roots about two feet lower, below low water 
level. Remains of a Dugong, which will be described presently, 
were found in this bed, and unearthed in the presence of two of 
us. Four tomahawks have also been obtained from this bed, as 
we are informed, and our information leads us to the opinion 
that it is almost certain that they were obtained in situ. These 
also will be described presently. 
(f) At the base of the estuarine blue clays is the horizon of 
the third peat bed, from a few inches up to five feet in thickness. 
Its upper surface is from ten feet to seven feet below low water. 
At the north-east end of the canal excavation, shown on the plan, 
and néxt to the upper dam, a very large number of tree stumps, 
as we are informed by Mr. W. Trickett, the overseer of the work, 
were unearthed, the majority being ten feet below low water. 
Of these, all but about three had been removed at the time of our 
visit (Nos. 1, 2, and 5).' This submerged forest is also reserved 
for detailed description. | 
(g) Below the third peat horizon is white running sand, with 
thin bands of brown peaty sand, extending to a depth of at least 
three feet. Canal excavations have not gone below this depth, 
but bores put down for the foundations of the Rickety Street 
Bridge showed that the strata underlying (g) are as follows :— 
8 ft. 6 in. Sand and mud. 
12 ft. 0 in. Blue clay resting on Hawkesbury Sandstone. 
(4) Remains of the Dugong.—One of the most important dis- 
coveries in connection with the Shea’s Oreek excavation is the 
discovery, by some of the workmen employed, of the bones of a 
Dugong. These were unearthed partly in the presence of one of 
us, near the junction of the two main tramlines running from 
