THE LONG-HORNED GOROPHIUM. 473 



when pressed by hunger, has no scruple in eating its own kind. It has many enemies, as is 

 sure to be the case when a little creature is produced in absolute clouds, when it is quite harm- 

 less, easily obtained, and excellent food. Sea-birds feed largely upon the Sand-hoppers, and 

 many land-birds are in the habit of passing much of their time upon the shore, and eating 

 their fill of these Crustacea. The green crab is a terrible enemy to the Sand-hopper, even 

 running it down in fair chase, as I have witnessed, and displaying wonderfnl ingenuity in 

 pouncing upon the active little creature just as it descends from its leap. Even a little beetle, 

 not a quarter its size, feeds upon the Sand-hopper, instinctively attacking it from below, where 

 it is comparatively undefended by its shelly coat. Sometimes three or four beetles will unite in 

 attacking upon a single Sand-hopper. The technical name of this beetle is Cillenum laterale. 



The Shore-hopper {Orchestia littorea) is also plentiful on sandy coasts, preferring those 

 where the sand is sprinkled with rocks. It may be known from the sand-hopper by its more 

 compressed body, the partly-clawed character of the two first pairs of legs, and the compara- 

 tively small size of the first pair. Though it hops on the sand, like the preceding species, and 

 has many similar habits, it is seldom found occupying the same locality, the sand-hopper 

 taking to one part of the coast and the Shore-hopper to another. 



Another strange-looking creature is the common Saxd-screw, an example of the next 

 family. In these creatures the antennas end in a lash-like point, called appropriately the 

 flagellum, or little whip. The Sand-screw is so called from the odd movements which it 

 makes when laid upon dry sand, wriggling along while lying on its side, and displaying an 

 awkwardness, in this respect, which contrasts greatly with the wonderful power and freedom 

 with which it can force its way through wet sand. In the course of its burrowings, it makes 

 many tortuous tracks in the sand, that are generally taken for the trace of some worm's passage. 



There are many fossil remains said to be the relics of certain worms, but which are now 

 thought by Mr. Albany Hancock to have been produced by some crustacean of similar habits 

 to the Sand-screw. He has given a most interesting account of this discovery, and the follow- 

 ing passages are extracted from his account : — " I went down to the beach, just as the tide was 

 leaving the spot where the broad tracks were usually in great profusion. The sand was quite 

 smooth, all irregularities having been obliterated by the action of the water. Hei'e and there, 

 however, the tracks had already made their appearance, but were as yet of very limited 

 extent, and there was no longer any difficulty in taking the whole in in one view, and, more- 

 over, the extremities were perfectly distinct. It was only necessary to vatch attentively, to 

 note the formation of the numerous and labyrinthine windings that had been so long a puzzle. 



"I had not long to wait before the sand at one of the extremities was observed to be 

 gently agitated, and, on this agitation ceasing, the track was found to have added nearly half 

 an inch to its length. In the course of two or three minutes, the sand was again put in 

 motion, and the track once more a little prolonged. These movements were repeated over and 

 over again, until it was quite clear, that the track -was formed by slow, intermitting steps, and 

 not, as might have been supposed, by one continuous gliding motion. Having satisfied myself 

 of this, I took up the morsel of sand at the end of the track, just as it was again becoming 

 agitated, and found that I had captured a small crustacean, the species of which was unknown 

 to me, though in general appearance it was not altogether unlike the common sand-hopper, 

 but not quite so long. I soon took in this way five or six specimens, all of the same species, 

 and all forming tracks of precisely the same character, namely, broad, slightly elevated, 

 flattened, and grooved. 



"While forming its track, the animal is never seen ; it moves along a little beneath the 

 surface of the sand, which it pushes upwards with its back, and the arch or tunnel thus 

 formed partially subsides as the creature presses forward, and, breaking along the centre, the 

 median groove is produced." 



A more slender and delicate-looking crustacean is Kroyer's Saxd-sorew, a creature 

 which possesses some of the same habits as the last-mentioned species. It burrrows horizon- 

 tally beneath the sand, like the common Sand-screw, but differs in its mode of action, the bark 

 always appearing above the sand. 



The Loxg-horxed Corophtem, a curious-looking and very interesting species, inhabits 



Vol. m.-W- 



