oS WOODWARDIA VIRGINICA. COMMON CHAIN-FERN. 



more clearly, the enlarged study, Fig. 2, is given. In further 

 explanation it may be noted that the veins in ferns often run 

 parallel with each other, or nearly so ; but in other cases they 

 form a sort of net-work, or, as it is said botanically, they anasto- 

 mose. In the case of these ferns this net-work is confined to 

 the parts of the frond, bordering on the costa or midrib of the 

 pinnule and its divisions, the outside portions having the veins 

 free, that is to say, not connecting with each other. The spaces 

 bounded by the small connecdng veins are called the areoles. 

 In our species, referring again to Fig. 2, we see that there is 

 but one series of these areoles, and which in our specimen bear 

 the fruit dots. There are other species of Woochuardia which 

 have several rows of these areoles, and those botanists who 

 regard the venadon or arrangement of veins as of great 

 structural importance, divide the genus into two, and then 

 make Woodiucirdia a mere synonym. The set with several rows 

 .they call Lorinseria ; and the other, which contains only our 

 present species, is called Anchistca, of Presl, who, in 1849, wrote 

 a work on Ferns, in which he made the venation the chief foun- 

 dation of his system of arrangement. The name Aiichiska is 

 from the Greek, signifying related to, and suggested by the fact 

 of its standing closely between other genera in the estimation of 

 the author. A large number of American botanists do not place 

 the same generic value on these conditions of tlie veins, and so 

 retain Woodiuai^dia for all of them ; but it must be confessed 

 that, besides the veining, the general appearance, which so often 

 is made to do duty in defining genera in other cases, exists 

 very strongly here. Our common chain-fern has the fronds all 

 alike ; other species of the genus have them different ; and yet 

 Lomaria taken from BlecJinum depends quite as much for its 

 distinction on the difference between the barren and fertile 

 fronds as on any other character. These facts may show the 

 student how careful the critical study of ferns must be. 



The rhizomes, or creeping underground stems of ferns — 

 indeed, the whole root system — has of late years been found to 



