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. Algae of the western Great Lakes area. Algae -- Lake States; Algae. is called the pseudoraphe and may be present in one or both valves. In some forms there are cross partitions or longitudinal partitions called septa. To identify Diatoms it is usually necessary to observe empty frustules or cleared cells. The wall markings, costae and puncta, the septa and the raphe must be discerned. A number of genera may be identified in the living or 'filled' condition, but it is ad- visable to follow a technique for clearing the frustule so that tax- onomic characters become apparent. Special terms are
. Algae of the western Great Lakes area. Algae -- Lake States; Algae. is called the pseudoraphe and may be present in one or both valves. In some forms there are cross partitions or longitudinal partitions called septa. To identify Diatoms it is usually necessary to observe empty frustules or cleared cells. The wall markings, costae and puncta, the septa and the raphe must be discerned. A number of genera may be identified in the living or 'filled' condition, but it is ad- visable to follow a technique for clearing the frustule so that tax- onomic characters become apparent. Special terms are used to describe and differentiate Diatom genera and species. Some of these appear in the following simple glossary. Diatoms are found in a variety of habitats, both acid and basic waters; on and in soil. Although some genera occur commonly in acid habitats, the majority are found in basic water and often occur in profusion with blue-green algae. They are macroscopically visible as brownish films on submerged objects, sand, and leaves of aquatic plants. Whereas most genera occur as solitary cells, many are filamentous and some are arranged in tufts and in at- tached, gelatinous colonies. (See reference, p. 660). 2- 1< 3-- 10 ,8. 10 t K ^ J. .2 .4. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Prescott, G. W. (Gerald Webber), 1899-. Dubuque, Iowa, W. C. Brown Co
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Keywords: ., bo, bookcentury1900, bookcollectionbiodiversity, booksubjectalgae