will be found adhering to the point of attachment a fringed oval object, which is part of a gill. Even in the lobsters, therefore, foot-locomotion is also partly subservient to breathing purposes. We have several species of both stalked and unstalked bar Goose Tree (Anseres arborei). From the Cosmographia Universalis' of Munster. nacles, of which Scalpellum vulgare (usually found attached to the base of those corallines called "lobster's horn") are abundant among the former, and Balanus hameri not unfrequent among the latter. The young of Scalpellum pass through very similar changes to those of the larvæ of Lepas. Our readers will remember the Lepas as that which is usually attached in thick clusters to old wreck and drift wood These are difficult to keep in aquaria, perhaps on account of their open-sea habits. Mr. Lloyd, however, managed to keep some alive at the Crystal Palace for nearly six months on a floating Larva of Lepas Australis in its last stage of development. a. Antennæ, with sucking disks. b. Carapace. c. Natatory legs. bottle, found at Bridport. This species usually goes by the common name of the "goose barnacle," from a very old notion (prevalent even among naturalists two hundred and fifty years ago), that from the shells the goose called the "barnacle" was produced. It was further believed to be borne by a peculiar kind of marine shrub, which was called the "goose tree" (Anseres arborei). Old Gerarde speaks most decidedly of having witnessed the whole process of development! The story is much older than his period, and was told and illustrated by Sebastian Munster, in his 'Cosmographia Universalis,' as long ago as 1572. The sessile barnacles appear to be more easily acclimatised in aquaria than the stalked. The latter are usually drifted about at sea, and possibly miss this artificial mode of aeration when confined in a tank. Fig. 211. Young Cirripede (enlarged) immediately after moulting the pupal carapace and assuming its natural position. a. Antennæ. c. Natatory unmoulted legs. The star-fishes, sea-urchins, and marine worms, like the crustacea, are capital adjuncts to what we may call the "still life" of an aquarium. They fill up as detail, make a good fore or background, and intensify the interest always felt in seeing objects of which we have heard or read alive for the first time. The star-fishes and sea-urchins are nearly related, in spite of their apparent unlikeness, both being grouped into an order called Echinodermata, or "spiny skinned." Both move by means of suckers, which are worked by a wonderful hydraulic apparatus from within the test or shell. In the sea-urchin the shell is made up of at least six hundred pieces, mosaicked together. Of these, five rows are perforated, and through these perforations minute suckers are protruded. They can be elongated when injected with suckers. water, which is strained off from the sea and admitted to the interior of the sea-urchin through a special plate called the "madreporiform tubercle." All these rows of feet protrude through the needle-like |