countries similarly
circumstanced. The Doras of Guiana[1] have been seen travelling over
land during the dry season in search of their natural element[2], in
such droves that the negroes fill baskets with them during these
terrestrial excursions. PALLEGOIX in his account of Siam, enumerates
three species of fishes which leave the tanks and channels and traverse
the damp grass[3]; and SIR JOHN BOWRING, in his account of his embassy
to the Siamese kings in 1855, states, that in ascending and descending
the river Meinam to Bankok, he was amused with the novel sight of fish
leaving the river, gliding over the wet banks, and losing themselves
amongst the trees of the jungle.[4]

[Footnote 1: _D. Hancockii_, CUV. et VAL.]

[Footnote 2: Sir R. Schomburgk's _Fishes of Guiana_, vol. i. pp. 113,
151, 160. Another migratory fish was found by Bose very numerous in the
fresh waters of Carolina and in ponds liable to become dry in summer.
When captured and placed on the ground, "they _always, directed
themselves towards the nearest water, which they could not possibly
see_, and which they must have discovered by some internal index. They
belong to the genus _Hydrargyra_ and are called Swampines.--KIRBY,
_Bridgewater Treatise_, vol. i. p. 143.

Eels kept in a garden, when August arrived (the period at which instinct
impels them to go to the sea to spawn) were in the habit of leaving the
pond, and were invariably found moving eastward _in the direction of the
sea_.--YARRELL, vol. ii. p. 384. Anglers observe that fish newly caught,
when placed out of sight of water, always struggle towards it to
escape.]

[Footnote 3: PALLEGOIX, vol. i. p. 144.]

[Footnote 4: Sir J. BOWERING'S _Siam,_ &c., vol. i. p. 10.]

The class of fishes endowed with this power are chiefly those with
labyrinthiform pharyngeal bones, so disposed in plates and cells as to
retain a supply of moisture, which, whilst they are crawling on land,
gradually exudes so as to keep the gills damp.[1]

[Footnote 1: CUVIER and VALENCIENNES, _Hist. Nat. des Poissons_, tom.
vii. p. 246.]

The individual most frequently seen in these excursions in Ceylon is a
perch called by the Singhalese _Kavaya_ or _Kawhy-ya_, and by the Tamils
_Pannei-eri_, or _Sennal_. It is closely allied to the _Anabas scandens_
of Cuvier, the _Perca scandens_ of Daldorf. It grows to about six inches
in length, the head round and covered with scales, and the edges of the
gill-covers strongly denticu