ity is unknown. See GUeNTHER, _Acanthopt.
Fishes_, vol. i. p. 282, where mention of the black humeral spot has
been omitted.]

[Illustration: THERAPON QUADRILINEATUS.]

In addition to marine eels, in which the Indian coasts abound, Ceylon
has some true fresh-water eels, which never enter the sea. These are
known to the natives under the name of _Theliya_, and to naturalists by
that of _Mastacembelus_. They have sometimes in ichthyological systems
been referred to the Scombridae and other marine families, from the
circumstance that the dorsal fin anteriorly is composed of spines. But,
in addition to the general shape of the body, their affinity to the eel
is attested, by their confluent fins, by the absence of ventral fins, by
the structure of the mouth and its dentition, by the apparatus of the
gills, which opens with an inferior slit, and above all by the formation
of the skeleton itself.[1]

[Footnote 1: See GUeNTHER'S _Acanthopt. Fishes_, vol. iii. (Family
Mastacembelidae).]

Their skin is covered with minute scales, coated by a slimy exudation,
and the upper jaw is produced into a soft tripartite tentacle, with
which they are enabled to feel for their prey in the mud. They are very
tenacious of life, and belong, without doubt, to those fishes which in
Ceylon descend during the drought into the muddy soil.[1] Their flesh
very much resembles that of the eel; and is highly esteemed.[2] They
were first made known to European naturalists by Russell[3], who brought
to Europe from the rivers round Aleppo specimens, some of which are
still preserved in the collection of the British Museum. Aleppo is the
most western point of their geographical range, the group being mainly
confined to the East-Indian continent and its islands.

In Ceylon only one species appears to occur, the

[Footnote 1: See post, p. 351.]

[Footnote 2: CUV. and VAL., _Hist. Poiss._ vol. iii. p. 459.]

[Footnote 3: _Nat. Hist. Aleppo_, 2nd edit. Lond. 1794, vol. ii. p. 208,
pl. vi.]

[Illustration: MASTACEMBELUS ARMATUS]

_Mastacembelus armatus_.[1] The back is armed with from thirty-five to
thirty-nine short, stout spines; there being three others before the
anal fin. The ground colour of the fish is brown, and the head has two
rather irregular longitudinal black bands; deep-brown spots run along
the back as well as along the dorsal and anal fins; and the sides are
ornamented with irregular and reticulated brown lines. This eel attains
to th