284 



H. is. SiLmmei 



almost contemporaneous, so that the assumption that the alkali 

 series and the basaltic series were derived from two separate and 

 distinct magmas is hardly tenable. The conclusions may be cited : 



" The authors believe that the Kainozoic volcanic rocks of Victoria 

 were derived from a common magma. First came the separation 

 and pouring out of the Older Basalts of the eastern and central 

 portions of Victoria. This left a magma moderately rich in 

 alkalies, and by some process of differentiation alkali magmas sepa- 

 rated out into at least three lesser magma basins, viz., at Omeo, 

 Macedon and Coleraine. On the exhaustion of these lesser magma, 

 basins, extrusion once more took place from the main reservoir, 

 giving the Newer Basalt series." 



It will be seen that the primary differentiation of the Macedon 

 rocks is considered to have been the separation of the alkali magma 

 from the basaltic magma, and that secondary differentiation of the- 

 serial and complementary types then ensued, and produced the 

 various members of the alkali series. 



(d) Lilydale Devonian Series. 



As stated earlier, four analyses of rocks from the Lilydale area 

 have been made at the Mines Department Laboratory, and these are 

 given in Table XIV. 



TABLE XIV. 



I. II. III. IV. 



SiO, 



AI2O3 



Fe,03 



FeO 



MgO 



CaO 



Na,0 



K2O 



H2O + 



H,0- 



CO., 



Tid. 



P.O.; 



Mro 



NiO 



CoO 



BaO 



Li^O 



S 



SO, 



CI 



Total 



Less = S 



Total 



99.93 99.94 99.47 99.15 



I. Dante, Dandenong Ranwe. 



II. Toacanito, Qnarry 1 m. N.E. of Lilydale. 



III. Dacite, Railway Cntting between Lilydale and Evelyn. 



IV. Toscanite, about 1 m. E. of Mooroolbark. 



