282 PROCEEDINGS OF SECTION C. 
syenite proper, occurs at the Heazlewood, all round Jupp’s 
at the 13-mile on the road from Waratah to Corinna. It is 
evidently a part, and a marginal part, of the Magnet and 
- Meredith Range of granite near its contact with the serpen- 
tinised gabbro and pyroxenite which are so well developed 
in that district. It is noteworthy that the rocks become 
excessively amphibolitic along this contact-line, and it is 
sometimes difficult: to determine whether chey were originally 
gabbroid or granitic. On the Heazlewood River, below 
Nickel Hill, is a typical dark-coloured hornblende-syenite, 
a quartzless rock composed of dominant orthoclase + plagio- 
clase + hornblende. The hornblende is abundant, and 
tends to occur in nests. Another variety from here, lighter 
in colour, has a moderate quantity of quartz in granophyric 
intergrowth with felspar, and little lumps and grains (also 
crystals) of gray sphene. Iron ores are scarce; no mica is 
discernible in either of these rocks. At the Heazlewood 
Mine is a hornblende-syenite with not quite enough quartz 
for a granite, containing green hornblende in fine crystals. 
Nests of actinolite occur in this rock. 
The absence of biotite in our hornblende syenites is a 
noteworthy feature. 
Augite-Syenite.—The Heazlewood also furnishes augite- 
syenite, consisting of orthoclase + plagioclase + augite + 
hornblende, + a little quartz. Augite-syenite also occurs 
in the biotite-granite of Schouten Main at the head of Frey- 
cinet’s Peninsula, on the East Coast, where the rock (called 
green granite locally) is composed of orthoclase + plagio- 
clase + augite + biotite. 
None of these syenites are independent massifs, but are 
invariably subordinate portions ef the great granite ranges. 
The syenite, in fact, may almost be regarded as a facies of 
the granite. 
Augite-Syenite Porphyry.—This rock occurs at the 
Gawler River, North-West Coast. It contains a little 
quartzo-felspathic ground-mass, with phenocrysts of alkali 
and lime-soda felspars, augite, and rarely biotite. It is a 
dark-green rock, much resembling a somewhat similar rock 
at Lynchford, except that the latter has porphyritic quartz ; 
and I have not seen any biotite in it. This rock, too, is 
more coarsely granular. A similar rock is met with at 
Beulah, Kentish. 
Pyrozene-quartz Porphyry.—This rather peculiar syenitic 
effusive occurs at Lynchford. It very closely resembles the 
Gawler rock, but has differences, as just mentioned, and 
seems to be connected either with the quartz-porphyry of 
