VOLCANIC ROCKS. 
45. BasauLtic LAVA. List No. Rs 1. 
Mount Shadwell. 
Rough, vesicular and slaggy looking: 
contains olivine sparingly, 
46. VesicuLar Basaur (Dolerite 
Lava). Map No. Rc 4. 
Leigh River (upper flow). i sheet 
64 N.E. 
Dark brown color. 
47. VESICULAR Basatt (Aname- 
site). Map No. Ra 96. 
West bank of Loddon. 4 sheet 
14 N.W. 
Vesicles very large. 
48. VESICULAR BASALT. 
Map No. Re. 10. 
Cargerie Creek, Leigh River. 
4 sheet 64 N.E. 
With some of the vesicles filled with 
carbonate of lime, 
49. Basarrt (Dense Dolerite). 
Map No. R. 8. 
Section 6, Tullamarine. } sheet 
2 S.W. 
Color light pinkish-grey ; fine-grained 
and vesicular on the surface. Vesicles 
containing specular iron and labra- 
dorite (?) 
50. SCORIA. Map No. M 7. 
Lot 10, section 11, Yuroke. 4 sheet 
2 N.W. 
Vesicles coated with “ hyalite.” 
51. Basarrt (Dolerite). 
Near Maimsbury. {sheet 9 N.W. 
Colorgrey; rough granular, “hyalite” 
in botryoidal aggregations occupying 
surface grooves and cavities. A good 
building stone. 
52. VESICULAR BASALT. 
Stone-Jug Creek, Spring Plains. 
4 sheet 13 N.E. 
Vesicles partly coated with carbonate 
of lime. 
58. Basa (Dolerite). 
Near Malmsbury. 4 sheet 9 N.W. 
This specimen is interesting, as show- 
ing the constituent minerals crystallized 
. 


27 
CASE V. 

out freely in irregular shaped cavities 
dispersed throughout the mass: the 
augite in dark green, prismatic needles, 
and the felspar in white rectangular (or 
rhombic ?) plates. There are also some 
dark-colored, hexagonal plates amongst 
them, with an iridescent surface (spe- 
cular iron?). This rock occurs in irre- 
gular patches and seams in ordinary 
. grey basalt, a portion of which may be 
seen on the reverse side of the speci- 
men. Extensive quarries opened in this 
basalt, or locally called “ bluestone,” 
have furnished much of the material 
used in the construction of the railway 
works near Malmsbury. 
54. VESICULAR BASALT. 
List No. Rs 1. 
Mount Shadwell, 
Contains large nests of olivine. 
55. VESICULAR BASALT. 
List No. Rs 1. 
Mount Shadwell. 
Dark grey, with crystalline grains of 
olivine. 
56. VESICULAR BASALT. 
List No. Rs 1. 
Mount Shadwell. 
Of a reddish-brown color ; it presents 
an appearance of eroded cavities rather 
than true vesicles. ‘These are coated 
with.a yellow, crystalline mineral (oli- 
vine ?). The specimen encloses a large 
nest of olivine in course of conversion 
by decomposition into mica (rubel- 
lane ?). 
57. BASALTIC LAVA. List No. Rs 1. 
Mount, Shadwell. 
This specimen represents a portion of 
the cast of a cylindrical hollow, or pipe, 
into which the lava has flowed. The 
central portion is entirely vesicular and 
scoriaceous, surrounded by concentric 
rings, or coats of dense texture, separ- 
able from each other, and presenting a 
striped surface on the planes of separa~ 
tion. Color reddish. Encloses a large 
fragment of felspar (oligoclase). 
58. BASALTIC DAVA. 
Mount Shadwell. 
Of a reddish color and scoriaceous 
character ; similar to above, except in 
form; contains embedded crystalline 
grains of olivine and also a large frag- 
ment of felspar (oligoclase). 
List No. Rs 1. 
