Abstract
UNDER the auspices of the Indian Medical Research Fund, Dr. N. Annandale and Mr. S. W. Kemp undertook in November, December, and January, 1918-19, an expedition to Seistan and Baluchistan with the object of discovering whether the disease Bilharziasis (or Schistoso-miasis) occurred in Seistan, and, in particular, whether any of the known molluscan hosts of the parasite were to be found in that region. So far as -the medical part of the inquiry was concerned the results were negative, but ths opportunity was taken to make a collection of the limited aquatic fauna of the country. The zoological results of the expedition are now in course of publication as a special volume of the "Records of the Indian Museum"under the title of "Report on the Aquatic Fauna of Seistan."In an introductory essay Dr. Annandale describes the physiographical conditions of the Hamun-i-Helmand, the basin into whirh the Helmand River flows, and which is occupied, according to season, by a large lake or by a series of lakes of variable area. Owing to the fact that in flood-time the Hamun overflows, by the Shelagh River, into the Gaud-i-Zirreh, "the Dead Sea of the Helmand system,"its waters do not reach a high degree of salinity, and it sustains a. fauna, impoverished indeed, but rich in comparison with that of true salt lakes. Dr. Annandale points out that although the Hamun occupies part of an ancient lake-bed, "there has been no biological continuity between the old lake and the recent one."The present lake may even have originated within historic times by a shifting of the course of the Helmand River. Dr. Annandale describes the Cyprinid fishes of the genus Dis-cognathus found in the region and, in collaboration with Dr. B. Prashad, the Mollusca. In the case of the latter it is pointed out that the fauna shows a mingling of Palasarctic and Oriental types and a noteworthy absence of Western Asiatic elements. The fauna, however, "is a starved one, in which only species of great adaptability can survive."
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Aquatic Fauna of Seistan. Nature 104, 453–454 (1920). https://doi.org/10.1038/104453b0
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DOI: https://doi.org/10.1038/104453b0