Our British Snails 



6i 



brown ; common. See accompanying illustration, 

 which shows the fringed branchial siphon which 

 drawls in food-bearing water, and the smaller 

 anal siphon by which it gets rid of undigested 

 matter. 



Unio pictonim. — More oblong and thinner shell, 



Freshwater mussel breathing and eating. 



yellowish, girdled with brown in the lines of 

 growth. Common. The specific name recalls 

 that gold and silver paint used to be sold in 

 these shells (or marine mussels) for illuminating 

 work. It is said to produce 220,000 eggs in the 

 three summer months. 



Unio [margaritana) margaritifer. — Shell solid 



