April, 1910.] THE VICTORIAN NATURALIST. 185 



dykes traversing the Silurian in the vicinity, being 18 feet 

 thick ; but is, unfortunately, becoming obscured from view, 

 owing to the growth of ornamental vegetation. Near this 

 second quarry were obtained the fossil fucoids recorded by 

 Blandowski in 1858, and now determined as Bythotrephis. 

 Specimens of the dyke-rock were secured, and also a few fossils. 

 Proceeding up the river, beyond Anderson-street, the party 

 reached the site of Hoyte's Paddock, where, strewn on the road- 

 side, were numerous fragments ready for the hammers of the 

 practical students of the party. Whilst the naturalists studied the 

 broken fragments, the natives studied the field naturalists. A fair 

 amount of success rewarded the efforts of the " stonebreakers," 

 and the specimens obtained were Trachyderma crassituha, 

 Chapm. MS. ; Camarot<jechia decemplicaia, Sow., sp. ; Nucleospira 

 australis, M'Coy ; Nucula melhournensis, Ch.; NucuUtes raac- 

 coyiamis, Ch. ; Palceoneilo, sp. ; Hyolithes spryi, Ch. ; Cycloceras 

 bullatum, Sow., sp. ; Encrinurus, sp., and (?) Ceratiocaris, sp. 

 (casts of spines and carapace). A search on the bank slope of 

 the river, a short distance beyond the Punt-road footbridge, 

 revealed the presence of a narrow dyke of a much-decomposed 

 igneous basic rock, full of dark biotite-mica crystals. This dyke- 

 rock is of a different nature to the more acid or granite-like dykes 

 usually met with in the Silurian, and, judging from occurrences 

 elsewhere, possibly older than the white felsitic dykes in the 

 Alexandra-avenue. It probably belongs to the ultra- basic lampro- 

 phyres, judging from the character of the green decomposition 

 products and the large proportion of biotite. The exposure seen 

 on this occasion may be one of the minor forks of a similar and 

 thicker dyke found in the neighbourhood of Chapel-street. This 

 concluded the business of the afternoon, and the members soon 

 afterwards dispersed, being fully convinced that it is not essential 

 to travel outside the zone of city sounds in order to study and 

 enjoy the problems of the past. — F. Chapman. 



EXCURSION TO WEST WARBURTON. 



The Foundation Day excursion (29th to 31st January), 

 originally intended for Gilderoy, in the valley of the Little 

 Yarra, was diverted to West Warburton by common consent of 

 those participating — viz., Messrs. Barnard, Mowling, Sutton, 

 and myself — the reason for the change being that all available 

 accommodation there had been early bespoken. Not wholly as 

 an afterthought. West Warburton claimed our attention as a centre 

 whence the large dacite area on the northern side of the Yarra 

 might be examined from the river to the top of the ridge by 

 traversing the valley of the Dee and cutting across the tributary 

 streamlets and up to " The Rock." This was the principal outing, 

 but the flats along the Yarra, the Silurian country to the east and 



