. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. 26 THREE CRUISES OF THE " BLAKE. away, the bar and tangles, which may be composed of a dozen to fifteen bundles, afford perhaps the most effective apparatus for collecting. The amount of ma- terial sometimes brought up baffles description, and it is no easy task to separate the specimens from the tan- gled mass in which they have been caught.^ The trawl is by far the most useful instrument in deeper water, where the bottom generally consists of ooze or fine mud, — the finer in proportion to the distance
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. 26 THREE CRUISES OF THE " BLAKE. away, the bar and tangles, which may be composed of a dozen to fifteen bundles, afford perhaps the most effective apparatus for collecting. The amount of ma- terial sometimes brought up baffles description, and it is no easy task to separate the specimens from the tan- gled mass in which they have been caught.^ The trawl is by far the most useful instrument in deeper water, where the bottom generally consists of ooze or fine mud, — the finer in proportion to the distance from land. The trawl first used in deep water was the ordinary beam-trawl of fish- ermen. When this form of trawl is used in shallow water, it is easy to guide it or to weight it so that it will always fall on its runners and drag successfully. At great dej)ths, how- ever, this form of trawl becomes ob- jectionable, from the impossibility, owino' to currents or the drift of the vessel, of guiding it, no matter how well-balanced it may be, so that it shall not land on the beam, a mis- hap that involves great waste of time, sometimes a whole day, from unsuc- cessful hauls. On the "Blake," a modification of the trawl was used Blake" Trawl. (^igs. 25, 26), which workcd admira-. 1 A tangle-bar of great efficiency, con- sisting of two poles tied in the form of the letter A, with cross-bar and lines with fishing-hooks, has been used with great success by ]\fr. Marshall, to collect halcyonoids. A very similar apparatus is also used by the natives of the Philip- pines to collect euplectella. The members of the United States Fish Commission have also introduced a number of admirable modifications of dredges, trawls, tangles, and sieves ; and, in fact, every part of the dredging appa- ratus now necessary for deep-sea work has been greatly improved by the ex- perience obtained during more than ten. Please note that these images are extracted from scanned page images that m
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