14 FERNS IN THEIR HOMES AND OURS. 



in travelling about the country in a trunk. From 

 curiosity, the little crown of this fern was planted ; 

 and it was matter of great surprise that in a 

 few weeks it developed several fronds. In cul- 

 tivation, all ferns of this habit require special 

 treatment. 



The frond of a fern represents something more 

 than the ordinary leaf of a plant. Often the 

 merest rudiments only of the leaflets (pintud) are 

 to be found in the young frond just unfolding; 

 while, as the frond unrolls, they develop and grow 

 to their perfect shape. Under favorable circum- 

 stances, the frond of some species seems capable 

 of indefinite development, as in Nephrolepis exal- 

 tata ; and, again, there is in some genera (Gleiche- 

 nia, for example) a tendency to a dichotomous 

 (forking) growth, which is often repeated from 

 the same frond during a second season. Another 

 remarkable feature of the fronds of some ferns is 

 the development of viviparous buds, either from 

 the under side, as in Cystopteris bulbifera, or 

 above, as in Asplenium bulbiferum. In Cystopteris 

 these bulblets fall off and grow during the second 

 season ; but in most species which have vivipa- 

 rous bulbs they remain attached to the frond, and 

 develop several leaves while still drawing their 

 nourishment from the parent frond. This habit 

 has a parallel in nearly all plants, from the lowest 

 Alga to the highest Phanerogams. It might be 



