lar canal. It will be seen after examining our drill, that it is typical of 

 the great class of mollusks which inhabit the sea, and are called Gas- 

 tropods because the foot or organ of locomotion is on the lower side of 

 the body, and the animal apparently crawls upon its stomach. The 

 name Gastropod is from the Greek and means stomach-footed. In some 

 marine shells the spire is long and tapering, in others it is short and 

 blunt, while in still others it is almost flat. The shells also vary, some 

 being fusiform, others cone-shaped, ovate, ladder-like, or ear-shaped; in 

 fact, the variety in form is almost endless. But however the shell may 

 vary, it can be described by the names which we have given to the 

 different parts of the drill." 



Having examined the shell of the drill, we turned our attention to 

 its occupant, the animal. This was not unlike those we had already 

 studied which lived in fresh water. Here were the same foot, tentacles, 

 head, rostrum, eyes, and operculum that we saw in the apple snail, only 

 they were of different color and shape. 



Professor Parker now led us along the shore to a place where several 

 large pools had been left by the receding tide. " Let us peer into the 

 water of this pool," said he, " and see if we can find a drill about its daily 

 work in its native home." As we gazed through the clear water, we 

 saw many beautifully colored seaweeds green, red, yellow, and brown 

 and darting here and there were several minnows, alarmed at our close 

 proximity. On the bottom of the pool, beneath a shelving rock, were 

 several " five-fingers," or starfish, while in another nook was a clam-worm, 

 with its hundreds of legs moving about. On the under side of the over- 

 hanging rock, several sea anemones, those flowers of the ocean, were seen, 

 with their tentacles expanded, ready to catch some unwary fish with 

 which to fill their capacious stomachs. Crabs, snails, and clams made 

 up the rest of the inhabitants of this miniature world. 



On the rock beside the sea anemones, we saw a drill, and hastily putting 

 his hand in the water, Harry drew it from the rock. But alas, as his 

 awkward hand grasped the shell and disturbed the waters of this quiet 

 pool, what a change took place! The sea anemones retracted their tenta- 

 cles, and became but a mere rounded lump ; the crabs and fishes sought 

 safety beneath the rocks and among the seaweed, and the drill, the animal 

 of which we had hoped to see, had withdrawn into its shell, and closed 

 the aperture tightly with its operculum. This operculum, or door, as the 

 name signifies, is a valuable part of the animal, enabling it to close the 

 aperture against all its enemies. It is placed on the upper surface of the 

 foot, and has a strong muscle attached to it. In large snails this muscle 

 is so powerful that the strongest man could not pull the animal from the 



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