It is an illustration of the eagerness with which, after the expedition of Alexander the Great, particulars connected with the natural history of India were sought for and arranged by the Greeks, that in the works both of ARISTOTLE and THEOPHRASTUS facts are recorded of the fishes in the Indian rivers migrating in search of water, of their burying themselves in the mud on its failure, of their being dug out thence alive during the dry season, and of their spontaneous reappearance on the return of the rains. The earliest notice is in ARISTOTLE'S treatise De Respiratione[3451], where he mentions the strange discovery of living fish found beneath the surface of the soil, "[Greek: tôn ichthyôn oi polloi zôsin en tê gê, akinêtizontes mentoi, kai euriskontai oryttomenoi?]" and in his History of Animals he conjectures that in ponds periodically dried the ova of the fish so buried become vivified at the change of the season.[3452] HERODOTUS had previously hazarded a similar theory to account for the sudden appearance of fry in the Egyptian marshes on the rising of the Nile; but the cases are not parallel. THEOPHRASTUS, the friend and pupil of Aristotle, gave importance to the subject by devoting to it his essay [Greek: Peri tês tôn ichthyôn en zêrô diamonês], De Piscibus in sicco degentibus. In this, after adverting to the fish called exocoetus, from its habit of going on shore to sleep, "[Greek: apo tês koitês,]" he instances the small fish ([Greek: ichthydia]), that leave the rivers of India to wander like frogs on the land; and likewise a species found near Babylon, which, when the Euphrates runs low, leave the dry channels in search of food, "moving themselves along by means of their fins and tail." He proceeds to state that at Heraclea Pontica there are places in which fish are dug out of the earth, "[Greek: oryktoi tôn ichthyôn]," and he accounts for their being found under such circumstances by the subsidence of the rivers, "when the water being evaporated the fish gradually descend beneath the soil in search of moisture; and the surface becoming hard they are preserved in the damp clay below it, in a state of torpor, but are capable of vigorous movements when disturbed." "In, this manner, too," adds Theophrastus, "the buried fish propagate, leaving behind them their spawn, which becomes vivified on the return of the waters to their accustomed bed." This work of Theophrastus became the great authority for all subsequent writers on this question. ATHENÆUS quotes it[3461], and adds the further testimony of POLYBIUS, that in Gallia Narbonensis fish are similarly dug out of the ground.[3462] STRABO repeats the story[3463], and the Greek naturalists one and all received the statement as founded on reliable authority.
Not so the Romans. LIVY mentions it as one of the prodigies which were to be "expiated" on the approach of a rupture with Macedon, that "in Gallico agro qua induceretur aratrum sub glebis pisces emersisse,"[3464] thus taking it out of the category of natural occurrences. POMPONIUS MELA, obliged to notice the matter in his account of Narbon Gaul, accompanies it with the intimation that although asserted by both Greek and Roman authorities, the story was either a delusion or a fraud, JUVENAL has a sneer for the rustic—
"miranti sub aratro
Piscibus inventis."—Sat. xiii. 63.
And SENECA, whilst he quotes Theophrastus, adds ironically, that now we must go to fish with a hatchet instead of a hook; "non cum hamis, sed cum dolabra ire piscatum." PLINY, who devotes the 35th chapter of his 9th book to this subject, uses the narrative of Theophrastus, but with obvious caution, and universally the Latin writers treated the story as a fable.
In later times the subject received more enlightened attention, and Beekman, who in 1736 published his commentary on the collection [Greek: Peri Thaumasiôn akousmatôn], ascribed to Aristotle, has given a list of the authorities about his own times,—GEORGIUS AGRICOLA, GESNER, RONDELET, DALECHAMP, BOMARE, and GRONOVIUS, who not only gave credence to the assertions of Theophrastus, but adduced modern instances in corroboration of his Indian authorities.
As regards the fresh-water fishes of India and Ceylon, the fact is now established that certain of them possess the power of leaving the rivers and returning to them again after long migrations on dry land, and modern observation has fully confirmed their statements. They leave the pools and nullahs in the dry season, and led by an instinct as yet unexplained, shape their course through the grass towards the nearest pool of water. A similar phenomenon is observable in countries similarly circumstanced. The Doras of Guiana[3471] have been seen travelling over land during the dry season in search of their natural element[3472], 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[3481]; 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.[3482]
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.[3483]
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 denticulated. Aided by the apparatus already adverted to in its head, this little creature issues boldly from its native pools and addresses itself to its toilsome march generally at night or in the early morning, whilst the grass is still damp with the dew; but in its distress it is sometimes compelled to move by day, and Mr. E.L. Layard on one occasion encountered a number of them travelling along a hot and dusty road under the midday sun.[3484]