196 



HARDWICKE'S SCIENCE-GOSSIP. 



[Sept. 1, 1S70. 



she tells us about iu her " Night Side of Nature," 

 are playing all over it ; but these little fireballs that 

 flash and wane, and flash again, and these still more 

 ghostly lights that seem to smoulder and creep, are 

 no evil portents, " warnings " from the unseen 

 world, unhallowed envoys from the charnel-house, 

 or from the ancient mariners who lie drowued deep 

 down beneath us in Davy Jones's locker, but lovely 

 little Cydippes, and exquisite little ocean-fairies, as 

 we shall see by-and-by. 



Fig. 17". Sarsia tubulosa, x 2. 



Carefully turning the net inside out over the 

 basin of water, the 'larger captives fall into it with 

 tiny splashes, while the small fry which cling to the 

 meshes, and get into the corners, must be patiently 

 brushed and swept off; it is even as well to rinse 

 the net itself in another vessel of water, to make 

 sure of securing the scores of larva?, crustaceans, 

 and tiny microscopic things that are certainly 

 there. And now let us cast the net again, and look 

 over this our first " take." Shooting to and fro in 

 the water is a translucent bell-shaped Medusa (fig. 

 177); it has four marginal tentacles arising from four 

 bulbs or tubercles, each bearing a little dark ocellus, 

 or eye-spot ; and hanging from the interior of the 

 crown of the sub-umbrella, is a remarkable append- 

 age which reminds us something of the tail of a 

 kite ; it is one of the Sarsiadce, a genus named after 

 the Norwegian naturalist Sars. The long, blue, 

 pendent kite-tail, which is really a " proboscidiform 

 peduncle," a kind of proboscis with a mouth at the 

 end, and containing the stomach, tells us at a glance 

 that it is Sarsia tubulosa, a species very plentiful in 

 the Solent, and which may be kept alive in confine- 

 ment for a fortnight without any trouble. 



Beginners first venturing to " fish for themselves " 

 in the great ocean of facts, or in that very deep well 

 at the bottom of which Truth lies hidden, will often be 

 amazed at catching in shoals, all manner of things 

 which are declared to exist only in the South Seas, 

 or at the North Pole, in the Persian Gulf, or the 

 Sea of Ohkotsk ; every day almost they will find 



such " distinguished foreigners " turning up by the 

 dozen on our own unromantic shores. Here, for 

 instance (fig. 17S), is a brilliant brightly-coloured 

 specimen of Tunis digitalis, supposed to belong of 

 right to the same latitudes as the seal and the 

 walrus, which we have now taken within fifty yards 

 of a family bathing-machine on our own prosaic 

 beach, in sight of the windows of the Pier Hotel. 



Fig. 1/8. Tunis digitalis, x 3. 



The next we find is a Thaumantias, a member of 

 a very abundant family. " Of all the Naked-eyed 

 Medusae, those belonging to this genus are most 

 common in our seas, swarming in countless myriads 

 in our bays and harbours. They are among the most 

 usual causes of phosphorescence." Their generic 

 characteristics are thus defined: — "Umbrella hemi- 

 spherical, in some species almost globular, in others 

 much depressed ; ovaries four, varying in form from 

 ovate to linear, conspicuous on the sub-umbrella in 

 the course of four simple radiating vessels ; margin 

 of umbrella with tentacula in variable numbers (from 

 4 to 200) according to the species, their bulbs always 

 ocellated ; stomach sessile, dependent from, and 

 almost always included within, the sub-umbrella ; 

 mouth with four lips, rarely fimbriated." 



Fig. 1"9. Thuumttutius cymbaloidea. 



The action of the cilia and the motion of the 

 nutrient fluid in the gastro-vascular canals of the 

 Medusae is beautifully shown by the microscope ; 

 the auditory and visual organs are equally wonderful 

 and attractive. For full details of the mechanism 

 and habits of these strange inhabitants of the great 

 waters, we must refer to Professor Edward Forbes's 



