The Mussels and Rock-eaters 



the good of the oyster beds, it is well to keep the mussels in check. 

 Thousands of bushels are taken yearly from the river mouths 

 of Great Britain to supply bait for the long-line fisherman. 



A tuft of coarse, black hairs attaches the mussel to its sup- 

 port. A word as to its origin and use will answer a very natural 

 curiosity which the sight of it always arouses. Nobody would 

 guess that it is an organ of locomotion, but that is precisely 

 what it is. The foot is a weak and flabby string of muscle, with 

 a gland at its base, which when compressed throws out a spray 

 of gelatinous substance which hardens into threads so strong 

 as to sustain a heavy weight. The mussel may wish to climb 

 up a pier. It has only to ejfect more threads upon a spot higher 

 up than its original point of attachment, and as these harden, 

 let go the old threads and hang on by the new ones. Pro- 

 gress by this method may not constitute a gait more speedy 

 than the minute hand of a clock makes, yet it accomplishes all 

 the mussel requires. Time is no object to him. I have tracked 

 an individual by a fringe of cast-off threads, but I have never 

 timed one. Though able by this means to be a free and inde- 

 pendent citizen, the mussel probably lingers near the place where 

 it first settled down. It feeds like an oyster on what bounty 

 the tides bring past the ciliated siphon tube. Bred in polluted 

 water, it is often the carrier of disease germs when eaten. At 

 spawning time it also causes sickness. 



The shells are polished outside and made into needle-books, 

 scent-bottle holders, pin-cushions, and various forms of jewelry, 

 to sell to tourists and other souvenir hunters. The average shell 

 is two or three inches long. 



Habitat. — Europe. Arctic seas to Cape Hatteras, Pacific 

 coast. 



A variety, pellucidus, brightly rayed with green and yellow 

 is often found with the typical form on our east coast. Another, 

 var. glomeratus, thrives in San Francisco Bay. It is two inches 

 long, and is constantly found in the fish markets of the city. 



M. Californianus, Conr., is pictured by Reeve as a deeply 

 grooved and rayed green and yellow shell when young, but at 

 maturity a blue-black giant, rough, without stripes, and eight or 

 nine inches long. It averages much smaller, and is brownish or 

 purple, with orange flesh. The Californian Indians set sharpened 

 points of this hard mussel shell in the tips of their harpoons. 



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