A Year at the Shore

by Philip Henry Gosse

All this time the tentacles have been set around the terminal margin, but now these are absorbed, and a new set rapidly spring from the basal segment. The saucers become very loosely attached; at length the end one breaks away and swims through the sea, as a true Medusa, though no more than a sixth of an inch wide, pumping as it goes in proper parental wise. Others quickly follow, and thus a colony of tiny swimming jelly-fishes are shooting hither and thither in the liveliest manner. Strange to say, these little Medusæ, which as to details differ much from their adult form, have been again described, under the name of Ephydra; all these appellations indicating the assumptions of various naturalists, who found the little creatures in their respective stages, without knowing their previous history, that each was an independent form of animal life.

CYDIPPE.

As the closer and more severe scrutiny of anatomical structure has induced modern zoologists to separate the Lucernaria from its formerly assigned alliance with the Sea-anemones, and to associate it with the Medusæ, it is interesting to remark that the scales of justice have been maintained in equipoise by the like shifting of a member from the Medusæ to the Anemones. The latter animal is one familiar to most haunters of the shore, and invariably admired as one of the most charming of the many lovely forms that throng the summer seas; it is the sweet little Beröe, or Cydippe.[131] Indeed at first sight you would be little disposed to admit the propriety of the transfer in this case, for certainly the active glittering globule of pure crystal appears to possess much more resemblance to one of the smaller Medusæ, the Sarsia, for instance,—than to a daisy or a beadlet. But naturalists look beneath the surface: and they find that, with important peculiarities, the internal economy of the Cydippe, and specially its digestive apparatus, are modelled rather on the type of the latter than of the former.

We will not, however, trouble ourselves now with these elaborate matters, but rather look at the exterior and obvious characters of the charming little pet, which is disporting itself in this vase of sea-water on our table. It is a globe of pure colourless jelly, about as big as a small marble, often having a little wart-like swelling at one of its poles, where the mouth is placed. At the other end there are minute orifices; and between the two passes the stomach, of a form which is flat, or wider in one diameter than in the other.

If the stomach be considered as the axis of the globe, and the two extremities as its poles, the meridians of longitude are well represented by eight narrow bands, situated on the surface, which do not, however, reach either pole. Along the course of each of these meridional bands are fixed at close intervals minute square moveable plates, whose outer edges are set with strong cilia, like the teeth of a comb. These are the locomotive organs, and most effective they are. They are used like the paddles of a steamer, the little animal beating the water with them in rapid and regular succession, their minute subdivision causing the rays of light, especially when in the sun, to play along these bands, with the most brilliant prismatic colours; while their vigorous strokes cause the globe to shoot hither and thither through the water with remarkable power.

Within the clear substance of the Cydippe, on each side of the stomach, there is excavated a capacious cavity, which communicates by a canal with the surface, near the equator. Within each cavity is fixed a tentacle of great length and slenderness, which the animal can at pleasure shoot out of the orifice, and allow to trail through the water, shortening, lengthening, twisting, or coiling it at will; or, on the other hand, quickly contract it into a tiny ball, and withdraw it wholly within the proper cavity. A peculiarity, which imparts an inexpressible charm to this apparatus, is, that, throughout the length of this attenuate white thread, short threadlets are given off at regular intervals, which can be coiled or straightened, lengthened or shortened, individually. They proceed only from one side of the thread-like tentacle, though, from the slight twisting of the axis, they seem now to project on one side, now on another.

It has been well observed that of the grace and beauty which the entire apparatus presents in the living animal, or the marvellous ease and rapidity with which it can be alternately contracted, extended, and bent at an infinite variety of angles, no verbal description can sufficiently treat. Fortunately this little beauty is so common in summer and autumn on all our coasts, that few who use the surface-net can possibly miss its capture. So lovely a creature is worthy of a poet’s description: it has received it.

“Now o’er the stern the fine-mesh’d net-bag fling,