842 Albert V. James : 



niaii times (16), stamps them as post Lr. Devonian. In one- 

 dyke (Dg) a few nodules of partly decomposed rock were found, 

 and this tells us tliat the dykes are not very ancient. It is, there- 

 fore, reasonable to jjlace them with the older basalt, because rocks, 

 of this age also occasionally show undecomposed nodules, and it 

 was at this period that vast quantities of basic magma were forced, 

 to the surface. 



Kainozoic Sediments. 



These will l)e briefly described under the following heads: — 



(a) Pre-olcler-basaltic river conglomerates. 



(b) Pre-newer-basaltic grits (Normal " Tertiary Grits."). 



(c) Eucalptus leaf beds. 



(d) Pre-nef\ver-basaltic river sediments. 



(e) Inter-newer-basaltic grits, conglomerates, etc. 



(f) Post-newer-basaltic grits, conglomerates and alluvium. 



(a) Pre-older-hasaltic river coiKjloinerate. — This is found in the- 

 extreme S.E. of the area, and has been described a1>ove. 



No fossils were found. Part of this deposit has been altered to- 

 quartzite, evidently by the older basalt. 



(b) Pre -newer -hamliiv grits and sands. — These are cenerally 

 stratified. Near Keilor, about two miles to the south, the grits- 

 are stratified, and marine fossils are abundant, but no fossils 

 have been found in the grits of this locality, with the exception of 

 the leaf beds descril)ed in the following paragraph. A close study 

 leaves little doubt that all these sandy deposits have been derive^l 

 from the Bulla granodiorite, the stratified and unstratified de- 

 posits apparently merging into one another. 



(c) Eucoli/pfus Leaf Beds.—Ow the left bank of Deep C'reek (See* 

 Plate XXXII.) a deposit of fine sands and very fine clay bands rests 

 above sands, which in turn rest on the upturned edges of the Silu- 

 rian sediments. These clay bands are overlain l)y other saiuly layers. 

 Ihe whole deposit is about 30 ft. in thickness, and is cov<?red by 

 more than lOO feet of basalt. The clay bands consist of two sheets. 

 a]x)ut 8 ft. in thickness, light blue resting on dark brown. Both 

 are fossiliferous, but the brown ai-e especially rich. The fossils are- 

 leaves of eucalypts, acacias, ferns, and other plants, together with 

 stems and fruits of unrecognised plants. The Eucalyptus leaves 

 have been described by Mr. V\. Patton (IT). From the delicately 

 even strata and the fineness of the clay, the deposit is evidently a 

 lake deposit. The old surface of the Silurian rocks rises to greater- 

 heights on all visible sides of the leaf beds, and this, together with- 

 the lithological character of the sediments, is strong evidence in? 



