624 THE LONG-HORNED COROPHIUM. 



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 following 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. Here 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, moreover, the extremities were perfectly 

 distinct. It was only necessary to watch 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 mediam groove is produced." 



An example of the tortuous track left by this animal is shown in the illustration. 



IN the right-hand lower corner may be seen a more slender and delicate looking 

 crustacean. This is KROYER'S SAND-SCREW, a creature which possesses some of the 

 same habits as the last-mentioned species. It burrows horizontally beneath the sand, 

 like the common Sand-screw, but differs in its mode of action, the back always appear- 

 ing above the sand. 



THE last figure in the illustration represents the LONG-HORNED COROHIUM, a curious- 

 looking and very interesting species, inhabiting the muddy parts of the sea-shore. This 

 creature is common in the summer and early autumn, at which times it walks boldly 

 upon the wet shore. During the later part of autumn and the winter it resides in holes 

 which it burrows into the mud clay, and in some places is so plentiful that the mud is 

 quite honeycombed by its tunnels. 



This species is 'very common on the French coasts, especially in the great mussel 

 preserves near Rochelle. M. D'Orbigny, who observed their habits closely, has given 

 a very animated account of their manner of feeding. 



The whole of the muddy deposit along the shores is inhabited by myriads of marine 

 worms, such as the nereis and lug-worm, and upon these the Corophium feeds. As the 

 tide rises, the worms ascend to the mouths of their burrows for the purpose of eating 

 the little animalcules that swarm on the shore. The Corophium wages continual war 

 against these worms, darts at them with surprising speed, fastens on them, and eats 

 them. Sometimes a great lug-worm will be surrounded by thirty or forty of these curious 

 Crustacea, all attacking it simultaneously, and forming a strange group as the worm 

 writhes in its endeavors to escape, and carries with it the small but pertinacious foes 

 under whose attack it is sinking. 



Hundreds of the Corophium may be seen beating the mud rapidly with their 

 enormous antennae for the purpose of discovering their prey, and the energy of the 

 movement and the evident excitement under which the creatures labor partake largely 

 to the ludicrous. They do not restrict themselves to the worms, being equally 



