Page:The Zoologist, 4th series, vol 4 (1900).djvu/342

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THE ZOOLOGIST.

imperceptible thread like that of a small Spider. The thread proceeded from the foot of the mollusc. When the foot was touched with the finger, a thread was drawn out as the finger was slowly moved away, and when the finger was lifted in the air the animal remained suspended to it for a long time, and for a great distance—more than three feet; even when moved about considerably, and otherwise somewhat severely tested, the creature did not fall; and more than a score were experimented upon, always with the same result. The animal—in some at least of these cases—hung, not in its native element, but in the air. On June 28th and 29th more weed inhabited by this animal was fished up, and Bélanger again observed the creature's spinning habits.[1] Speculating upon the use of the thread, he remarks that the creature, born, living, and reproducing on floating weed, incessantly tossed with more or less violence by the very deep ocean, would be lost, when detached by a wave, had it not this faculty of spinning a silk which, like a cable, holds it to its habitat. On July 8th further weed was fished up, but the molluscs were now less numerous; and, having been out of the water some time when experimented upon, but few remained suspended after the weed had been shaken. Providing himself with a bucket of sea-water, however, Bélanger was able to make several observations; some of the animals adhered to his finger, and hung therefrom, both in the air and in the water. An individual which had lowered itself from the weed, on being placed in the water, remained suspended, and, though moved from one side of the bucket to the other, made to sink to the bottom and lifted up again, it still retained its hold. At length the observer allowed the weed to float on the surface, and after some time, to his great satisfaction, he saw the animal ascend by its thread, and replace itself upon the frond from which it had been suspended. Others which were at the bottom of the bucket, on being moved with a branch of weed, attached their silk to it;

  1. The author refers also to a bundle of weed, containing a quantity of eggs, supposed, no doubt erroneously, to be those of Litiopa. The eggs were united by numerous threads similar to those of the mollusc; each egg was attached by a particular thread, and the whole mass was so strongly fastened together that it was with difficulty that a part was detached. This structure, it can hardly be doubted, was the "nest" of the little Gulf-weed Fish, Pterophryne.