510 
THE CRETACEOUS ROCKS OF TRITAIN. 
“ Andalusite. — One or two apparently colourless grains showed 
the delicate rose-pink to almost colourless pleochroism of this 
mineral, such as may, for example, be observed in many of the 
Andalusites of the Cornish granites. 
“ Ana tase. — Deep blue irregular fragments are present, which 
probably are referable to this mineral, but this cannot be stated 
with certainty. 
“ Glauconite is present in deep-green rounded grains, evidently 
internal casts, but giving no clue, to the organisms from which 
they were derived. 
“ Muscovite occurs in thin silvery-white flakes, polarizing in very 
low tints, while brown flakes of equal thinness must probably be 
referred to biotite. 
“The residue from this rock is of particular interest in consequence 
of the presence of Andalusite and Fibrous Tourmaline, these not 
having been obtained from the residues in the Isle of Wight, East¬ 
bourne, Folkestone, or the Midlands, and being well-known con¬ 
stituents of the granitic rocks in the south-western counties. 
“ Beer Stone (this example was collected by the writer 
from the Beer Quarries).—The material exceeding *5 mm. only 
included a few silicified snow-white organic fragments and some 
rounded quartz grains. 
“ The rest consists of silicified Foraminifera of no definitely recog¬ 
nisable shapes, flakes of muscovite mica, numerous rods of glau¬ 
conite, angular grains of quartz, and a few minute crystals (one of 
them perfectly terminated at both ends) of Tourmaline, and also 
one fragment of the columnar type previously mentioned.’’ 
W. F. Hume. 
Examination of Washings. 
Specimens of the chalk of this zone from Beer Head (Devon), 
Dover, and Hitchin were washed. That from Beer Head was 
hard and in a semi-crystalline condition, and the results were 
less satisfactory than in the case of the other two, but sufficient 
evidence was obtained to show that it differed but little from the 
others. 
Shell-Fragments. —These were all of Inoceramus-sheW. Many 
were large pieces showing the prismatic structure ; the remainder 
were chiefly prisms. There were also a few ossicles of Star¬ 
fish, and in the Dover specimen one or two Echinoderm plates 
and a few fragments of rather large spines occurred. No fish 
teeth, scales, or coprolites were observed, and no sponge- 
spicules. 
