. Annals of the New York Academy of Sciences. Science. Pig. 1.—Eel larva. September 13. About natural size a kind of lurching movement. When advancing slowly, its height, which insures contact with a large surface of water, allows it to move with precision,—in the sense that a pencil held vertically in the first in-bent curve of the fish's body will not be touched by the fish as it advances,— in other words, that the fish does not show lost or slipping movements. When resting, the young fish arranges itself in irregular vertical coils, thus probably keeping its balance. When disturbed (snout t
. Annals of the New York Academy of Sciences. Science. Pig. 1.—Eel larva. September 13. About natural size a kind of lurching movement. When advancing slowly, its height, which insures contact with a large surface of water, allows it to move with precision,—in the sense that a pencil held vertically in the first in-bent curve of the fish's body will not be touched by the fish as it advances,— in other words, that the fish does not show lost or slipping movements. When resting, the young fish arranges itself in irregular vertical coils, thus probably keeping its balance. When disturbed (snout touched with a pencil point), the fish retreats tail foremost, the head remain- ing passive: if disturbed again, the head will be quietly drawn back, the motion starting as before with a withdrawal of the tail and hinder trunk. If disturbed repeat- edly, however, the fish will either swim about actively or draw itself into a close coil (Fig. 2). This position, however, it will sometimes assume without artificial stimulus, e. g., after it has become "tired" swimming around the wall of a circular jar. Leptocephalus from time to time secretes con- siderable mucous: this remains attached but is finally "brushed off" (in a mass) at the tail end of the body. Such a bit of slime will occasionally be touched by the young eel when swimming about; it is evidently dis- tasteful, for the young fish speedily frees itself, shaking its head in a curiously energetic Pig. 2.—Eel larva. Retracted position. 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 York Academy of Sciences. New York, New York Academy of Sciences
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectscience, bookyear1877
