May, 1908.] THE VICTORIAN NATURALIST. 1 1 



shales rise liigh on the flanks of Mt. WilHam, and are much 

 indurated. They are then succeeded by diabase or greenstone, 

 which forms the main mass of the range. There can be but 

 httle doubt that the Ordovician is older than the diabase, and has 

 been silicified by its intrusion. It may be noted that this 

 diabase outcrop, which is several miles in extent, and includes 

 the aboriginal quarries, is not marked on the geological map. 

 At the site of the aboriginal quarries we found highly inclined 

 platy jointing occurring in the diabase, and it is this jointing 

 which has determined the site of the quarries, as it has facilitated 

 the first shaping of the axes. Hereabout small quartz veins were 

 common in the diabase, and some we saw were over an inch in 

 diameter. Some of the blocks of greenstone were slightly 

 vesicular, though nothing approaching the agglomerates of 

 Photograph Nob at Heathcote were seen. About half a mile 

 north of the quarries the diabase is bounded by granite, and 

 along the contact zone a small amount of mining has been done. 

 From the presence of the quartz veins in the diabase near its 

 junction with the granite, it seems probable that the granite is 

 the younger rock, but further observation is necessary to see if 

 granite veins can be found cutting through the diabase. 

 The succession, then, seems to be — 



Granite 

 over Diabase (greenstone), 

 over Ordovician shales, &c. 



At Lancefield itself we find modern volcanic rocks extensively 

 developed, and these yield the rich soil of the district. The 

 volcanic rocks cover practically all the country traversed by the 

 railway from here to Melbourne. 



All of the party will, I am sure, unite with me in thanking our 

 Lancefield friends for their kindness, for without their guidance 

 we should not have seen one-half of what we did see. — T. S. 

 Hall. 



[The illustration given herewith is from a photograph by Mr. 

 J. H. Harvey, taken during the excursion. It shows one of the 

 chipping places, just distinguishable as a heap of small stones on 

 the summit of the hill, with an outcrop of rough stones, from 

 which the tomahawks were shaped, in the foreground. It was 

 to this heap, and the fallen she-oak tree, Mr. Barnard referred in 

 his article on page 115 of the Naturalist for November last. — 

 Ed. Vict. Nat.'] 



Botany. — A course of University Extension Lectures on 

 botany by Professor Ewart, D.Sc, Ph., is announced to be given 

 in the Biological School, University. Particulars can be obtained 

 from Miss Jean White, Biological School. 



