SEA-SIDE STUDIES. 



313 



to and fro in the water, and with which it can bring the food to its 

 mouth. As soon as a snail or other small animal falls among the fringes, 

 these close around it and move it toward the mouth, where it is soon 

 swallowed, the soft parts digested and the hard parts excluded. By- 

 means of its broad base or " foot," the sea-anemone attaches itself 



Fig. 2.— AcTiNiiE OR Sea-Anemones which live in the Sand and are often unattached. 

 1. Peachia fia^tata, Gosse.— 2. Edward.na callimorpMa, Gosse.—Halocampa chrysantheUum, 

 Goese— the lagt mostly buried in the sand. 



firmly to the rock or shell on which it rests, and seldom moves from 

 the spot which it has chosen, although it can effect locomotion by 

 means of its " foot." By this it clings so firmly to the rock that it 

 sometimes suffers itself to be torn in two rather than let go its hold. 



The main cavity of the body in the sea- 

 anemones is divided by septa or partitions, 

 which run from the top to the bottom, and 

 from the outer wall to the stomach. These 

 partitions or septa are in pairs, and the 

 number is some multiple of six. By what 

 principle of selection this constant num- 

 ber was introduced we may be curious 

 enough to inquire, but we must not expect 

 to receive at once a perfectly satisfactory 

 answer. 



The partitions above mentioned are the 

 infolding of the bodv-wall of the animal, 

 and are essentially the same as the wall itself. Toward the top of 

 each partition there is a hole, permitting free passage for the water to 

 flow from one chamber to another. 



Fig. 3.— Crops-Section of a Poltp. 

 OR Sea-Anemone, showing the 

 Septa. 



