134 Reports and Proceedings—Geological Society of London. 
Glensaul district it is not possible to draw a sharp line of distinction 
between the two rock-types, some of the calcareous gritty tuffs 
passing into nearly pure limestone; but the authors retain the terms 
to indicate the close connexion between the two districts. 
The fossils from the Shangort and Tourmakeady Beds, which have 
been examined by Mr. F. R. Cowper Reed, show a close resemblance 
to those of the Tourmakeady district; but the finding of certain 
additional forms, especially ileus armadillo and Niobe sp., has 
impressed upon Mr. Reed the close connexion between this fauna 
and that of the Orthoceras Limestone of Sweden, and has convinced 
him that it is rather of Arenig than of Llandeilo age. The conclusion 
is in conformity with the field-evidence, for at one point beds of 
gritty shale, containing Radiolaria and Graptolites (indicating the 
zone of Didymograptus hirundo), occur associated with the tuff of the 
Shangort Beds. The relegation of the Shangort and Tourmakeady 
Beds of Glensaul to the Arenig would imply a similar age for those of 
the Tourmakeady district. 
The Glensaul district contrasts strongly with that of Tourmakeady 
as regards the character of the crystalline igneous rocks, which are all 
quartz-felsites, and the authors believe them to be entirely intrusive. 
Mr. F. R. C. Reed describes one species of Jl/enus, one of Niobe, 
one of Vileus, two of Bathyurus, three of Cheirurus, one of Phomera, 
one of Lnerinurus, one of Phacops, and a new species of Bathyurellus. 
He also describes three species of Orthis, one of Hyolithes, one of 
Rafinesquina, one of Camerella, and one of Porambonites, and his 
conclusions as to the evidence which is furnished by the fauna 
regarding the age of the beds are mentioned above. 
2. ‘*On the Gneisses and Altered Dacites of the Dandenong 
District (Victoria), and their Relations to the Dacites and to the 
Granodiorites of the Area.” By Professor Ernest Willington Skeats, 
Se. A.RC.S., B-G:S. 
The area described lies about 25 miles south-south-east of 
Melbourne. The earlier literature is discussed, and it is shown that 
the early geological surveyors regarded the dacites as Paleozoic 
‘traps’ passing gradually into the granodiorites. Professor J. W. 
Gregory first described the rocks as dacites, probably of Lower 
Tertiary age, resting upon the denuded surface of the granodiorites 
and of the adjoining Lower Paleozoic sediments. ‘The author 
describes the field-relations of the rocks, and shows that gneiss 
occurs between the dacite and the granodiorite in places. Elsewhere 
at the contact the dacite appears slightly altered. The contact with 
the plutonic rock is everywhere abrupt. No foliation or banding 
occurs in the granodiorites, but acid veins pass from the junction into 
the altered dacite and also cut across the foliations of the gneiss. 
The field evidence, therefore, shows that the dacites are older than 
the granodiorites, and also that the gneiss was formed before the 
intrusion of the acid veins. Chemical analyses of the rocks and of 
the coloured minerals of the dacites are recorded. 
The chemical evidence indicates that slight differentiation of 
a magma took place: the dacite was first erupted, and, following 
