. Fig. 23.—Early stages o^ Simulimn : a, group of larvre ; b, larva , Mg., a European species; c, group of pupa3; (/, pupa in its case ; c, oupa (after Miall). Life-history. The larva of Simulium is aquatic, living mostly in mountain streams, in the stems of water-plants (PheUandrium, Siuin, etc.), or attached by the tail-end to rocks covered by swiftly running water, their bodies being held vertically. Their chief requirement is that the water shall be well aerated, but the water itself need not necessarily be pure, as the larva of S. reptans has been found in Europe swarming in st
. Fig. 23.—Early stages o^ Simulimn : a, group of larvre ; b, larva , Mg., a European species; c, group of pupa3; (/, pupa in its case ; c, oupa (after Miall). Life-history. The larva of Simulium is aquatic, living mostly in mountain streams, in the stems of water-plants (PheUandrium, Siuin, etc.), or attached by the tail-end to rocks covered by swiftly running water, their bodies being held vertically. Their chief requirement is that the water shall be well aerated, but the water itself need not necessarily be pure, as the larva of S. reptans has been found in Europe swarming in streams contaminated by sewage. The food of the Simulium larva is microscopic, diatoms and desmids. The power of attachment is very considerable, its swimming power very weak. It is cylindrical, soft-skinned, nari'owed in the middle, eulai'ged at the end, possessing pairs of eye-spots, two large fan-like branched antennae, and on the underside of the first thoracic segment a foot-like protuberance with bristly booklets or teeth ; this structure forms a sucker and is constructed by the coalescence and development of the first pair
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Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectdiptera, bookyear1912
