342 Albert V. J amies : 



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

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

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

 fore, reasonable to place 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. ' , 



Kalnozoic Sediments. 



These will be briefly described under the following heads: — 



(a) Pre-older-basaltic river conglomerates. 



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



(c) Eucalptus leaf beds. 



(d) Pre-newer-basaltic river sediments. 



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



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



(a) Pre-oldei'-hasaltic. river congloiuerate. — This is found in the* 

 extreme S.E. of the area, and has been described above. 



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

 quartzite, evidently by the older basalt. 



(b) Pre -newer -ha saliic r/rits and sandi?. — These are generally 

 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 described in the following paragraph. A close study 

 leaves little doubt that all these sandy deposits have been derived', 

 from the Bulla granodiorite, the stratified and unstratified de- 

 posits apparently merging into one another. 



(c) Eucalyptus Leaf Beds. — On the left bank of Deep Creek (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 by other sandy layers.. 

 The whole deposit is about 30 ft. in thickness, and is covered by 

 more than 100 feet of basalt. The clay bands consist of two sheets- 

 about 8 ft. in thickness, light blue resting on dark brown. Both 

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

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

 stems and fruits of unrecognised plants. The e^ucalyptus leaves 

 have been described by Mr. B. Patton (17). 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 iiv 



