41 



1st. The Historic Period ; 

 Sad. The Pre-historic Period ; 

 3rd. The Post-pliocene Period. 



1st. In the historic period I do not approach nearer than 

 Romano-British or Roman times, and I have included the first period 

 not only because it affords illustration of the accretion of materials 

 ■within some portion of the basin dm-ing a given period, but also 

 from the fact that by a curious circumstance there are preserved 

 to us some of the testacea and other remains of that time. 



In making an excavation for a drain near Sydney Buildings two 

 stone cofl&ns were discovered about 12 feet under the surface, one 

 of which contained the well-preserved skeleton of an adult male, 

 the other that of a younger female. That they were persons of 

 some importance may be infen-ed from the circumstance that after 

 the bodies had been placed in the coffins the latter were filled in 

 to the surface with poimded crystalline carbonate of lime, which 

 must have been purposely brought from some mineral district, 

 the nearest being that of the Mendips, where we know the Romans 

 had important mineral works. As a general rule the Roman city 

 lies at a depth of about 12 feet beneath the present surface, and 

 in this instance we have these coffins covered up to that depth. 

 But before this happened and when they were still near the surface 

 land shells of the period had found their way throuo-h the 

 interstices of the lids, whilst some small Brachiopoda, corals and 

 other fossils derived from the inferior oolite were washed in and 

 found in a thin ochreous deposit on the top of the carbonate of 

 lime. 



The shells thus discovered consist of — 



Helix rotundata 



„ hispida 



„ pulchella 

 Clausilia nigricans 

 Limax 



Carychium minimum 

 Pupa muscorum 

 Aplysia ? 



Zonites nitidulus 



„ ci-ystallinus 

 Zua lubrica 



„ allied to ditto 

 Achatina acicula 

 The fry and ova of various 

 shells 



