Page:Natural History, Mollusca.djvu/333

Rh parts of the creation. Many of these animals have occasionally fallen under my notice; but amid pursuits which rendered it impossible to attend either to their examination or preservation. I have, however, preserved a memorial of one, as it appears to form a new species, in a tribe of which no individual has yet been observed within the limits of the British seas. It belongs, apparently, to the genus Salpa. . . . "The mode in which the republic is linked together, is observed to be constant in each species; and it is sufficiently remarkable in this one, to distinguish it from the rest of the genus, as far as it is yet described. Each individual adheres to the preceding, by a regular sequence of superposition, lengthwise; so that the whole forms a long, simple chain, the adhesion continuing as in the ovarium, for some time after hatching. They were found from the middle to the latter end of August, and always linked together. It is probable that their separation takes place at a later season of the year, but I did not observe them in that state. The individual is amongst the most simple in shape of those yet described, presenting an oval-lanceolate and slightly rhomboidal flattened figure, without appendages. The anal opening is of a bright brown hue, and circular, being placed at some distance from the extremity; and when the chain is linked together, all these apertures are directed the same way. The animal is perfectly hyaline, and tender, and the adhesion of the chain so slight, that the individuals are easily separated. The act of swimming is known to result from the introduction and emission of water by each animal: and as the republic swims together by an undulating