PHfYSICA L .SPECTS
strata probably include Tertiary and Cretaceous sediments, resting on
a substratum of gneiss, and possibly slates. The Tertiary beds are
probably all miocene, corresponding in age to the Siwaliks, and consis
of sandstones or clays, with sometimes rubbly limestone. The under-
lying strata are probably the sandstones of the Umia group, of neocomian
or Lower Cretaceous age. Remnants of Deccan trap and Lameta (Upper
Cretaceous) may occasionally intervene between the two formations.
The Deccan trap is exposed in the western part of the Dhandhuka
tdauka. The outlying mahdl of Gogha in Kathiawar consists of Deccan
trap, laterite, and Siwalik beds, the latter forming the island of Piram,
renowned for its fossil bones and fossil wood. The saline earth in the west
of Viramgam was at one time used for the manufacture of saltpetre.
The District as a whole is open and poorly wooded. The chief trees
are mango, rdyan (Mimuusops hexandra), mahudi, and nim (Melia
Azadirachta). The Modasa hills bear inferior teak and bamboo, and
also produce the khair, babul, pipal (Ficus religiosa), bordi (Zizyphus
Jujuba), and khdkra (Bzutea frondosa). Many of the trees and shrubs
supply food, medicines, and materials for dyeing and tanning. Gum
from the khair and bdbul is eaten by the poorer classes. The pipal and
bordi yield a wax much used by goldsmiths for staining ivory rods, and
the leaves are eaten by buffaloes. The berries of the mahud are boiled
with grain, and the leaves of a creeper called dori (Leptadenia reticulata)
form a favourite article of food with the Bhils. From its seed soap-oil
is extracted. Of flowering plants the principal types are Hibiscus,
Crotalaria, Indigofera, Cassia, and Ipomoea.
Tigers are almost extinct. Leopards are found in Modasa, and
wolves in the low-lying salt lands near the Nal. Wild hog are common.
Gazelle and barking-deer are also met with. The smaller kinds of game
are obtained during the cold season in great numbers, especially quail,
duck, and snipe. Fish abound.
Except in the southern tracts lying along the sea-coast, the District,
especially towards the north and east, is subject to considerable varia-
tions of temperature. Between the months of November and February
periods of severe cold occur, lasting generally from two days to a week.
During the hot months, from February to June, the heat is severe; and
as the rainfall is light, the climate in the rainy season is hot and close.
October is the most sickly month. The mean temperature is 81°, the
maximum indoors being 115° and the minimum 47°.
The rainfall varies but slightly between the central portions of the
District and the outlying tracts. Dhandhuka and Gogha are the driest.
The maximum average rainfall is 34 inches at Modasa, and the mini-
mum 27 at Dhandhuka. The annual rainfall for the twenty-five years
ending 1902 averaged 29 inches. In consequence of the ill-defined
channels of the western rivers and the low level of the ground in