;U4 . Morris Morris: 



Middle Dacite Series; and. lastly (•)), the Upper or Hyperstheiie- 

 Daeite Series, whieli is the normal Daeite. (Plate XXX.. Fi^'. 

 '.].) No cliff section o( these junctions is known, hut in every 

 instance the iit)ove (jrder of ascent was the observed order. 



It is probable that in the first instance the junctions between 

 these series occupied about the same level east and w^est right along 

 the north flaidv of the range, Init. owing to the downthrow of the 

 Evelyn and the Olinda faults at its north-east extremity, the Middle 

 Daeite Series (d) has been depressed to form the bed of Olinda 

 Creek at that place, and the ITpper Daeite Series (e) is also found 

 at a low level in the fault valley. (Plate XXX., Fig. 2.) 



Pefroloff/ra/ CJtaracter. — This is a dark, slate-coloured, compact, 

 lirittle rock, showing phenocrysts of quartz freely, felspar less so, 

 hiotite in hexagonal tiakes. pyrites and garnets occasionally, and 

 numerous fragments, mostly igneous, the rest sedimentary. 



Phenocrysts consist of quartz and orthoclase, idiomoiphic. gene- 

 rally corroded, and often brecciated owing to flow movement. The 

 quartz is more alnuidant than orthoclase, the latter often shows 

 rhombic sections, with diagonal extinction. Plagioclase is subor- 

 dinate to ortlioclase. is idiomorphic. and apparently ranges from 

 oligoclase to laliradorite ; l)iotite occurs in grains and flakes, 

 bleached, and flexed by flow movement; garnet is common, often 

 chloritised ; iron oxide is seen in irregular grains, and there is 

 also a secondary oxide associated with and derived from tlie l)iotite; 

 apatite and zircon aie present as accessories. 



The ground mass is abundant, glassy to cryjitoci-ystalline. and 

 lines of flow fre(iuently are well developed, with fragments of the 

 phenocr_vsts corresponding therel^o. Numerous inclusions of vol- 

 canic material and hornfels are present. 



(Jheinicdl Com position . — In this rock the sub-alkali character is- 

 pronounced. It is mucli I'icher in CaO and MgO, and poorer in 

 alkalis than tlie toscanite series. It lias over 68 per cent, of SiOj, 

 and is, therefoi'e. a daeite. 



V^)\■ these and other reasons, whicli appear latei'. this series has 

 been called " The Lower Daeite Series." 



t1,—Tht Miihllc Darifr Serirs. 



If wt. regai-d the Dandeiiongs as built up cf three layers, then 

 the prcsnit series (//) ((institutes the srcund layei'. except at the 

 north-east corner, wliere it has been faulted down to stream level. 

 It rises, abruptly, in most cases, above the " Dandenong Agglome- 



