NESSO´NIS LACUS(ἡ Νεσσωνὶς λίμνη), a lake of Pelasgiotis in Thessaly, lying east of Larissa, now called Karatjaíror Μαυρολίμνη.In summer it is only a marsh, and contains very little water, but in winter it is filled by the overflowing of the Peneius. When the basin is filled, its superfluous waters are conducted by a channel into the lake Boebeis, now called Karla. (Strab. 9. p. 440; Leake, Northern Greece, vol. 1. p. 445, vol. 4. p. 403.) Strabo regarded the lakes Nessonis and Boebeis as the remains of the great lake which covered Thessaly, before the waters found an outlet through the vale of Tempe to the sea; but he is mistaken in saying that Nessonis is larger than Boebeis. (Strab. 9. p. 430.) Nessonis received its name from a town Nesson, which is mentioned only by Stephanus B. (s. v. Νέσσων).