Natural history and propagation of fresh-water mussels . Fig. 3.—The drunim m1 li:,Wayne. r.\Lalni a ition of fresh-water mussels 1\tiKt Canal near Fortinarkab!> dense popula- FiG. 4.—Parts of the Miami and Erie Canal affordexcellent environments for Fic 5.—Construction of wing dams in the upper Mississippi River often renders conditions unfavorable for mussels thatpreviously throve in such sections of the river. FRESH-WATER MUSSELS. 95 the stronger development of the hinge teeth which aid in keeping the two valves of theshell in perfect apposition. Since a river presents fr
Natural history and propagation of fresh-water mussels . Fig. 3.—The drunim m1 li:,Wayne. r.\Lalni a ition of fresh-water mussels 1\tiKt Canal near Fortinarkab!> dense popula- FiG. 4.—Parts of the Miami and Erie Canal affordexcellent environments for Fic 5.—Construction of wing dams in the upper Mississippi River often renders conditions unfavorable for mussels thatpreviously throve in such sections of the river. FRESH-WATER MUSSELS. 95 the stronger development of the hinge teeth which aid in keeping the two valves of theshell in perfect apposition. Since a river presents from source to mouth conditions of varying suitability for anyform of animal life, there will usually be found in some measure a longitudinal successionof mussels. Shelford (1913, p. 122) gives a table showing the longitudinal sequence ofeight species of mussels in the Calumet Deep River. If one goes down a river from its headwaters, making collections of mussels atvarious points, many species may be found at each place, but some species first encoun-tered may disappear before the upper waters are passed. Others appear here or thereand perhaps disappear as one proceeds still farther down. The mussel fauna of thedifferent sections of the stream are characteristi
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Keywords: ., bookcentury1900, bookdecade1920, bookpublisherwashi, bookyear1921
