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Numbers of this species may be seen in rivers, as well as in irrigated fields and estuaries, preying upon fishes, which however it refuses in a state of captivity. It is of timid and peaceful habits. A large female, after having been confined upwards of six months in a glass vessel filled with water, brought forth eleven young ones in the manner noted above under Acrochordus javanicus. During the process she lay motionless on the bottom of the vessel, the anterior part of the abdomen was retracted towards the vertebral column, while the muscles of the posterior part were in activity. Shortly after the parturition she expired under a few spasmodic movements, and also two of the young ones died in the course of about two hours, after having, like the rest, shed the integuments. In length they varied from 6 inches to 63. The living nine presented a singular appearance : they remained a little way below the surface of the water coiling themselves round the body of an adult male, which was also kept in the vessel, occasionally lifting the heads above the surface to breathe, at the same time resisting the efforts of the senior to free himself. Fishes and aquatic insects were refused, in consequence of which the young ones expired from inanition in the course of less than two months.

HIOMALOPSIS PLUMBEA, Boie. Syn.--IIypsirhina, Wagler.

Hypsirhina hardwickii, Gray: Illust. Ind. Zool.

Homalopsis plumbea, Schlegel. Iridescent dark brownish-or greyish-olive above, uniformly or with small irregular black spots; the two or three lowest series of scales yellowish, each scale spotted or edged with brown ; lips and throat yellow ; scuta and scutella yellowish white, the former in some partially edged with black, the latter with a black central zig-zag line ; iris grey; pupil elliptical, vertically contracted by the light ; tongue whitish.

Scuta 125 to 126 ; Scutella 36 to 44. HI ABIT.- Pinang.

Java. The head is broad, ovate, depressed; the muzzle blunt, the nostrils small triangular, with a slit towards the lower margin of the nasal ; the single anterior frontal broad triangular ; the rest of the crown shields are of normal form. The eye is small, placed in a half lateral half

vertical position, enclosed by two post-orbitals, one elongated præ-orbital, and beneath by the fourth upper labial; the frenal is very small, tetragonal; the upper labials eight, rather high ; lower labials ten; on both jaws the shields increase in size towards the angle of the mouth. The chin is covered with two pairs of elongated shields and a few gulars. The mouth is small; the posterior upper maxillary tooth longer than the rest, furrowed, and the anterior lower maxillary teeth also exceed the following. In addition to the fixed teeth there are several accessory series. The trunk is nearly cylindrical, slightly depressed, covered with small rhombic scales, smooth, and not imbricate, disposed on the anterior part in 19, on the posterior part in 17 longitudinal series. The tail is short, conic, tapering and slightly prehensile. Two individuals, taken at different times in rivulets in the valley of Pinang, in habits resembled II. rhinchops. The larger was of the following dimensions : Length of the head,

inch. Ditto ditto trunk,

1 5 Ditto ditto tail,

0 29

0 ft. 13

1 ft. 87 inch. Circumference of the neck, 15, of the trunk, 24, of the root of the tail, 11 inch.

HOMALOPSIS LEUCOBALIA, Schlegel, VAR. (See Plate XL. Fig. 5.)

Young.-Above light brownish olive, or greenish grey with single irregular distant brown spots ; lips and throat whitish yellow; the lowest three or four lateral series of scales, and the abdominal surface greenish white or pearl-coloured.

Adult.Uniformly blackish olive above, otherwise like the young. Iris dark brown; pupil elliptical, vertically contracted by the light. Tongue whitish.

Scuta 130 to 148; Scutella 26 to 37. Habit.—Pinang, Malayan Peninsula.

The head is very broad, depressed, and the muzzle blunt ; the rostral broad, hexagonal, very slightly arched beneath; the superior margin borders the single small elongated anterior frontal, which is of a narrow hexagonal form, broader behind, where it is wedged in between the two broad frontals. The nasals are rather large; nostrils small

crescent-shaped; the vertical very broad, short, hexagonal ; occipitals
large, elongated with a pair of very broad shields on each side, below
which the temples are covered by three smaller shields. The eye is
very small, in a half vertical position, with two post-orbitals, one præ-
orbital, which extends to the large oval nasal; frenal none, or, when
present, excessively minute. Of the five large upper labials, the ante-
rior is the smallest and borders the nasal ; the second the præ-orbital,
the third the orbit, and the lower post-orbital, the fourth and fifth the
temporals. The lower rostral is very small, triangular. The seven or
eight inferior labials are much smaller than the upper. The two pairs
of mentals are very short. The mouth is small; the teeth are very
strong, short and of nearly equal size, except the furrowed last upper
maxillary tooth and the anterior teeth of the lower jaw, which are
longer than the rest. The trunk is robust, back slightly raised in the
centre, the sides sloping, their lower half compressed, the abdomen
broad, arched. The scales are smooth, rhombic with rounded points,
slightly imbricate ; those of the sides have the points bent inwards
and firmly adhering to the skin, so as to appear hexagonal. On the
anterior part of the trunk they are disposed in 27, on the posterior in
25 longitudinal series. The tail is short, robust, tapering and some-
what prehensile. In the male the sides are compressed, very high in
the middle, and the lower surface is flattened, very broad, more so than
is the posterior part of the abdomen. In the female it is shorter, the
sides less high, and the lower surface less broad. The largest male of
a considerable number was of the following dimensions :
Length of the head,..

O ft.
Ditto ditto trunk,...

1
Ditto ditto tail,..

0 2

07 inch,

102

[blocks in formation]

Circumference of the neck, 13, of the trunk, 24, of the root of the tail, 14 inch. With the exception of its colours, the present offers no difference from H. leucobalia, from the rivers of Timor. At Pinang it is numerous not only in fresh water and estuaries, but in the sea at some distance from the shore, where it sometimes occurs in fishing nets. It is of sluggish, not fierce habits, and feeds upon fishes and crustacea, aquatic and pelagic. In a young female the oviduct enclosed

4 white cylindrical eggs, which when they were observed contained but yolk; each measured about an inch in length.

HOMALOPSIS HYDRINA, N. S. (See Plate, Fig. 4.)

Adult.-Ash-coloured above with a few scattered black spots on the neck; the back and tail with numerous transversal black bands; the lips, sides and abdomen uniformly pearl-coloured. Iris ashy; pupil elliptical, vertically contracted by the light ; tongue small, whitish.

Scuta 161; Scutella 31.

Young.--Resembling the adult, but the ash-colour of a much lighter shade.

Scuta 153; Scutella 35.

HABIT.-Sea off Pinang, and the Malayan Peninsula.

The head is moderately distinct, elongated, depressed, oval with rounded, blunt muzzle; the rostral shield moderate, hexagonal ; its lower margin with a central minute tubercle, on each side of which a triangular impression. The upper margin of the minute triangular lower rostral presents a central cavity, and two lateral elevations fitting into the margin of the upper rostral. A similar contrivance in the pelagic serpents enables them hermetically to close the mouth. As in H. leucobalia, the single small anterior frontal is elongated hexagonal, broader behind, and enclosed by the rostral, the nasals, and the frontals. Although the nasals are placed laterally, the small arched linear nostrils open vertically, and send a slit to the posterior margin of the shield; the frontals are hexagonal, smaller than the latter ; the vertical is the longest of the crown-shields, very narrow, hexagonal, pointed at both extremities, but broader behind; the supra-orbitals are small, narrow; the occipitals are broken up in minor shields : viz. two postoccipitals, in size equal to the occipitals, and a minute conical interoccipital, enclosed by the four shields, with the broader extremity wedged in between the occipitals. Each temple is covered with two pairs of large shields, of which the lower borders the fifth, sixth, and seventh upper labials. The eye is very minute, prominent, almost vertically placed, surrounded by two post-orbitals, of which the lower is broad pentagonal, meeting beneath the elongated single oblique præorbital. Thus none of the upper labials border the orbit. The frenal is moderate, pentagonal. Of the seven upper labinls the anterior three

pairs are much smaller than the rest, which suddenly become very large and deep, so as to make the margin of the lip very bulging in a downward direction. The lower ten or eleven labials are smaller than the upper, except the sixth, which is the largest. The chin with two pairs of shields of which the anterior is very elongated; the throat with numerous minute scales. The mouth is small, the dentition resembles that of liomalopsis leucobalia, Var. The trunk would be orbicular, but for the narrow flattened abdomen, the scuta of which are angulated, forming on each side a sharp ridge. The scales are very small, smooth, on the neck disposed in 33, successively in 37, but near the root of the tail in 29 longitudinal series. Those of the back are rhomboidal with rounded points; those of the sides lanceolate with the point bent inwards, so as to appear truncated, each scale leaving a small square interval, in which appears the naked skin. The tail is short, much compressed, tapering and slightly prehensile. In the male the sides are very high, and the lower surface very broad, as noted under H. leucobalia, Var. On the broadest part there are as many as 21 longitudinal series of scales. In the female this organ is shorter, the sides less high, and the abdomen less broad.

Of three individuals observed, two were captured in fishing stakes placed in the sea off the shores of Keddah, a third was washed on shore by the waves on the coast adjoining my house at Pinang. The largest male was of the following dimensions : Length of the head,

O ft. 0 inch.
Ditto ditto trunk,

1 45
Ditto ditto tail,

0 2

1 ft. 73 inch. Circumference of the neck, g, of the trunk, 19, of the root of the tail, , of the middle of the tail, 1 ; two eighths from the apex, inch.

It moved actively and without difficulty on the sand, and did not offer to bite. In one examined the stomach contained remains of two small pelagic fishes. In general appearance and colours the present is more closely allied to the pelagic serpents than any other known species. Whether it exclusively inhabits the sea, or, like Homalopsis rhinchops, enhydrus, and leucobalia, as an occasional visitor, must be a matter of future investigation.

(To be concluded in our next.)

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