PERNS OP GREAT BRITAIN. 23 



bank or other tree. Several species of Polypody are used 

 for medicines in other countries, as the P. Calaguala, the 

 root of which has an oily and disagreeable taste, but 

 which in America is highly valued for its alterative pro- 

 perties. The various species, of which there are immense 

 numbers, adorn the tropical lands of the Western He- 

 misphere, where they attain great luxuriance; and our 

 Common Polypody, which is found aU over Europe, 

 grows in many parts of Asia and America, either this 

 or a very similar species being one of the commonest 

 ferns in many of the woods and hedges of North Ame- 

 rica. Dr. Joseph Hooker says that in Calcutta the 

 Hindoos boil the young tops of a polypodium Tvith 

 their shrimp-curries. In some countries the plants of 

 this genus are much larger than the British species. 

 Mr. Bennett, in his account of the South Sea Islands, 

 mentions among other ferns, a species of Polypody 

 which he found at Mahiatea, growing in abundance on 

 a high mound built of coral stones. He says that the 

 natives called it Atua-buua, or Pig's-god, and beheved it 

 to exercise a watchful care over the weU-being of these 

 animals. 



Several little variations occur in the form of our 

 Common Polypody, the lobes being more or less cleft, 

 or acute, or serrated. One of the most important is 

 that termed Cambricvm, the Welsh Polypody, in which 

 the lobes become broader, and are again irregularly 

 lobed and toothed. This is always barren. The va- 

 riety Hibernicum, or Irish Polypody, has a broader 

 twice or thrice-pinnate frond, and is fertile. It is an 

 exceedingly handsome form of the fern. The French 



