136 
The Queensland Naturalist August, 1941 
On the talus slopes of these hills I found heaps of oyster 
shells and Avicula pectens, the ancestors of the common 
pectens or fan shells of our own beaches. The oysters occurred 
in such heaps as to remind one of native kitchen middens, 
as they lay white and bleached on the desert sands. 
Coelenterata, or corals, mainly of the branching type were 
common in large patches, which had at one time either been 
reefs, or the central hub of some local sea current. Amongst 
the most outstanding of the many fossils, is the echinodermata 
or sea urchin, which is especially prolific about the weathered 
gorges and low level salt lakes in the vicinity of Jerabub. In 
this particular area local block faults have formed precipitous 
valleys into which gorges have been carved. Layer upon 
layer of overhanging limestone, residuals and ragged tall 
slopes, falling away into the blue, misleading “jewels” of salt 
saturated water, twinkling in mockery amidst the green 
papyrus and scattered palm trees. 
Travelling west from Egypt, along the coast line of Libya, 
we find that the low undulating coastline gives place to small 
rugged cliffs and headlands, greatly distorted in the eyes of 
the observer owing to the lack of comparison with other objects. 
Here the land rises back from the coast in a series of steps, 
each one representing a layer or group of layers in the lime- 
stone. This horizontal stratification was used to advantage by 
the ancient Greeks and Romans who carved small man-holes 
through the upper layer and led these to large caves below, 
thus protecting themselves from the blinding dust and sand 
storms which are an almost constant feature of this unfor- 
tunate but interesting land. 
