[Footnote 1: See Paper "_on some Species of Fishes and Reptiles in Demerara_," by J. HANDCOOK, Esq., M.D., _Zoological Journal_, vol. iv. p. 243.]
In those portions of Ceylon where the country is flat, and small tanks are extremely numerous, the natives in the hot season are accustomed to dig in the mud for fish. Mr. Whiting, the chief civil officer of the eastern province, informs me that, on two occasions, he was present accidentally when the villagers were so engaged, once at the tank of Moeletivoe, within a few miles of Kottiar, near the bay of Trincomalie, and again at a tank between Ellendetorre and Arnetivoe, on the bank of the Vergel river. The clay was firm, but moist, and as the men flung out lumps of it with a spade, it fell to pieces, disclosing fish from nine to twelve inches long, which were full grown and healthy, and jumped on the bank when exposed to the sun light.
Being desirous of obtaining a specimen of the fish so exhumed, I received from the Moodliar of Matura, A.B. Wickremeratne, a fish taken along with others of the same kind from a tank in which the water had dried up; it was found at a depth of a foot and a half where the mud was still moist, whilst the surface was dry and hard. The fish which the moodliar sent to me proved to be an Anabas, and closely resembles the _Perca scandens_ of Daldorf.
[Illustration: THE ANABAS OF THE DRY TANKS]
But the faculty of becoming torpid at such periods is not confined in Ceylon to the crocodiles and fishes, it is equally possessed by some of the fresh-water mollusca and aquatic coleoptera. The largest of the former, the _Ampullaria glauca_, is found in still water in all parts of the island, not alone in the tanks, but in rice-fields and the watercourses by which they are irrigated. There it deposits a bundle of eggs with a white calcareous shell, to the number of one hundred and more in each group, at a considerable depth in the soft mud, under which, when the water is about to evaporate during the dry season, it burrows and conceals itself[1] till the returning rains restore it to liberty, and reproduce its accustomed food. The _Melania Paludina_ in the same way retires during the droughts into the muddy soil of the rice lands; and it can only be by such an instinct that this and other mollusca are preserved when the tanks evaporate, to re-appear in full growth and vigour immediately on the return of the rains.[2]