THE SHELL-ANIMALS 415 



laying months are May to August, and the popular saying 

 that oysters are not edible except in the months with the 

 letter " r " in their names, i.e., September to April inclusive, 

 is connected with the fact that in the months without " r" 

 the animals are likely to be filled with eggs. The oysters are 

 the most valuable mollusks, and the business of raising oysters 

 is worth millions of dollars a year. From Chesapeake Bay 

 alone more than twenty-five million bushels of oysters are 

 marketed annually. 



The marine clams and scallops are of great importance, 

 and attempts are now being made to cultivate them. Unless 

 this becomes commercially successful, the natural supply 

 will soon be exhausted. Such investigations are under the 

 auspices of the United States Bureau of Fisheries and of 

 certain state experiment stations; and these scientific 

 institutions deserve the necessary financial support. 



Certain large land-snails have long been esteemed as 

 delicacies. There were snail-gardens in Roman times, but 

 now the snails are widespread pests in vineyards and gardens 

 of Europe. 



Preparations from snails were once used for coughs, con- 

 sumption, malaria, asthma, dropsy, and almost all other 

 diseases. In some rural regions of England people still 

 believe that snails are of medicinal value. 



Numerous marine snails (gasteropods) are used as food in 

 various parts of the world. Squids and cuttle-fishes are 

 eaten by poor people in some countries. 



Sepia or Indian ink has been mentioned as obtained from 

 cuttle-fishes. The famous Tyrian purple once used for 

 coloring royal robes came from another mollusk. 



Shells of mollusks are of great ornamental value. They 

 have long been sought by conchologists (collectors of shells), 

 and more than $100 has often been paid for a single rare 

 specimen. 



Natives of the South Sea islands use shells for a great 



