THE MEDITERRANEAN NATURALIST 
Edom,, Moab, and the volcanic district of Jaulan 
and Hauran; aud (v) the maritime plain borde- 
ring the Mediterranean. 
The most ancient rocks (of Arckean age) are 
found in the southern portion of the region; 
they consist of gneissose and schistose masses 
penetrated by numerous intrusive igneous rocks. 
They are succeeded by the Lower Carboniferous 
beds of the Sinaitic peninsula and Moabite table- 
land, consisting of bluish limestone with fossils, 
which have there counterparts chiefly in the 
Carboniferous Limestone of Belgium, and of a 
purple and reddish sandstone (called by the Au- 
thor ‘the Desert Sandstone,’ to distinguish it from 
the Nubian Sandstone, separated from the Cre- 
taceous age), lying below the limestone. The 
Nubian Sandstone, separated from the Carbo- 
niferous by an enormous hiatus in the succes- 
sion of the formations, is probably of Neocoinian 
or Cenomanien age, and is succeeded by white 
and gray marls, and limestone with flint, with 
fossils of Turonian and Senonian ages. The Mid- 
dle Eocene (Nummulitic Limestone) beds appear 
to follow on those of Cretaceous age without a dis- 
cordance; but there is a real hiatus notwithstan- 
ding the apparent conformity, as shown by the 
complete change of fauna. In Philistia a calca- 
reous sandstone in which no fossils have been 
observed is referred to the Upper Eocene; for 
the Miocene period was a continental one, when 
fruiting and fiexuring was taking place, and the 
main physical features were developed — e.g., the 
formation of the Jordan- Arabah depression is 
referable to this period. 
In Pliocene times a general depression of land 
took place to about 200-300 feet below the present 
sea-level, and littoral deposits were formed on 
the coasts and in the valleys. To this period 
belong the higher terraces of the Jordan-Arabah 
valley. The Pliocene deposits consists of shelly 
gravels. Later terraces were formed at the epoch 
of the glaciation of the Lebanon Mountains, 
when the rainfall was excessive in Palestine and 
Arabia. 
The volcanoes of the Jaulan, Hauran and 
Arabian Deserts are considerad to have been in 
active operation during the Miocene,, Pliocene, 
and Pluvial periods; but the date of their final 
extinction has not been satisfactorily determined. 
341 
The vegetation of the house terraces 
of Malta. 
Every body who lives or has iived in Malta has 
doubtless observed our characteristic oriental 
looking flat-topped houses. These afford capa- 
cious terraces whereon rain water collects and is 
afterwards conducted along their imperceptible 
slopes by means of clay pipes into our wells. All 
these terraces and generally also the walls which 
surround them do not keep their original colour 
but are often encrusted with lichens which after a 
rain shower exhibit themselves as layers of black, 
grey and yellow patches, contrasting with the deep 
green of the mosses and algae, which find favoura- 
ble conditions for growth in the wet ground. 
Besides these, there are certain phanerogams so 
urban in their habits that they are very often found 
on the cornices of the terraces or in protected corn- 
ers These are for the most part, as would be ex- 
pected, plants the seeds of which are transported 
by the wind or by birds. 
Botanists go far into the country in search of 
flowers and interesting plants whdst they have an 
unknown vegetation growing over their heads, 
which has been altogether neglected till now. 
Though these humble plants cannot boast of a 
brilliant foliage or of pompous corollas they are 
not the less interesting, and uncared for they 
deserve not to be simply throdden upon. 
These lichens are an important factor in render- 
ing our houses damp proof, for they coat our 
limestone which is so muck subject to atmospheric 
influences with a protective layer, which effectual- 
ly prevents it from absorbing too much water in 
winter and from the direct action of the sun rays 
in summer. 
The number of species usually to be found does 
not vary much, nor it is very abundant. 
To begin with the higher forms, the phanero- 
gams generally met with in corners or on the 
coruices are: — 
Koniga ma> ittuna Br. 
Polycarpon tetraphylhim L. 
Conyza ambigua JD.C. 
Sonchus ctsper OIL 
