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SNAKES                                                          603

1.    The head is covered with large shields.

2.    Four large shields are found on either side of the lower lip.

3.    The scales in the central row down the back are large and hexagonal.

4.    The tail is round.

5.    The plates under the tail like those on the belly are entire and not
divided.

Banded Krait.—This is larger than the common krait, and grows to a
length of six feet and rarely seven feet. It occurs in India in the north-east
as far south as the basin of the Mahanadi river. In addition to the dis-
tinguishing characteristic marks of the common krait, the banded krait has
alternate black and yellow bands across the back.

The hydrophidae or sea snakes are found in the vicinity of the sea coasts.
Their eyes are very small, and their tails are flattened. Their nostrils are
situated on the top of the snout so as to enable them to breathe freely while
swimming or in the sea. Their belly plates are not broad and the scales on
their backs are dull and tuberculated. Although poisonous, they are inoffen-
sive by nature and do not as a rule bite man. The commonest species of
these snakes is Enhydrina Valakadien.

The viperidse or viperine snakes have a peculiar broad, lozenge-shaped
head usually covered with small scales, a narrow neck and a short tail. The
pupils of their eyes are vertical slits. The females give birth to living young.
These snakes are divided into two main classes, viz. pit vipers and pitless
vipers. Pit vipers are those which have a pit or a deep depression on each
side of the head between the eye and the nostril, and usually occur in hills.
Their bites are seldom fatal to man. Pitless vipers are those which have no
pit on the head. They have broad plates on the belly extending right across
and small scales on the head similar to those on the body. The two species
of pitless vipers which occur in India and are dangerous to man are the
Daboia or Russell's viper (Daboia or Vipera Russellii or Daboia Elegans)
and the saw-scaled viper, Phoorsa or Echis (Echis Carinata),

Daboia or Russell's Viper.—This is also called the chain viper, and is
found throughout India except in the Gangetic valley. It is called Gkonus
in Marathi and Khadchitro in GujaratL It has a buffi or light brown colour,
and ^grows to a length of four to five and a half feet. It is stouter than any
other poisonous snake in India, and narrows towards its tail, which is short.
Its head is flat, heavy and triangular, and has a white V-shaped mark with
its apex pointing forward. Its nostrils are bigger than those of any other
Indian snake* It has three rows of black or brown spots along the back, the
outer two rows consisting of spots ringed with white edges. Its body is
whitish with dark semHunar spots. It produces a terrible hissing sound
when about to attack its victim.

The entire broad plates on. the belly, the small scales on the head and
the shields beneath the tail divided into two rows are sufficient to identify
this snake.

Saw-scaled Viper, Phoorsa or Echis (Echis Carinata).—This is called
Plioorsa in Marathi and in Gujarati, and Afai in Urdu. It is a small snake,
growing to a length of one-and-a-half to two-and-a-half feet, and is brown,
or brownish-grey in colour. It occurs in the State of Bombay, Rajasthan,
Sind and other sandy parts of India. It has a triangular head, the upper
surface of which is covered with a white mark resembling a bird's footprint
or a cross. It has a continuous white wavy line along each flank of the
back. Diamond-shaped areas of a darker colour are situated between the
upper curves of the two wavy lines. The back is covered with rough or
keeled scales which produce a peculiar rustling sound when