. Circular. Agriculture; Agriculture; Entomology. 4 N. J. Agricultural Experiment Stations, Circular 139 widespread over a large part of San Francisco Bay. Before owners were aware that anything was wrong, the borers had completely cut off at the mudline the piling of many piers, terminals, and other marine structures (fig. 1). Based upon the costs of repairs and re- placements made necessary through these attacks, a careful estimate of the damage done during 1920 and 1921 in San Francisco waters alone gives a figure in excess of $15,000, Fig. 1. Municipal Wharf and House, Benicia, Califo
. Circular. Agriculture; Agriculture; Entomology. 4 N. J. Agricultural Experiment Stations, Circular 139 widespread over a large part of San Francisco Bay. Before owners were aware that anything was wrong, the borers had completely cut off at the mudline the piling of many piers, terminals, and other marine structures (fig. 1). Based upon the costs of repairs and re- placements made necessary through these attacks, a careful estimate of the damage done during 1920 and 1921 in San Francisco waters alone gives a figure in excess of $15,000, Fig. 1. Municipal Wharf and House, Benicia, California Collapsed October 7, 1920. (Reproduced by courtesy of San Francisco Marine Piling Committee from their report, 1921, pi. 1, fig. 3.) The two most important reasons why the European pileworm is so much more dangerous than the native species are: first, that it in- vades the brackish water area and comes much closer to fresh water than do other borers; and second, that it requires but a very short time to reach sexual maturity, and in a single season produces enormous numbers of young. What it is and How it Lives Before describing the outbreak of Teredo navalis in Barnegat Bay last summer, let us consider briefly some of the most important points in the make-up and the life history of the animals. The figure on the title page shows a number of young specimens of Teredo navalis, sexu- ally mature, as removed from their burrows. Three specimens of the native shipworm, Bankia fimbriata, are shown above for comparison. Note the two delicate shells which partly cover the front or anterior end, and between which lies the foot (fig. 5). By far the greatest. 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 New Jersey Agricultural Experiment Station; New Jersey Agricultural College. Experiment Station. New Brunswic
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Keywords: ., bookcentury1900, booksubjectagriculture, booksubjectentomology
