TUBERS OF NEPHROLEPIS. 



WHEN changing to a larger pot, the tropical sword fern 

 {Nephrolepis exaltata), a number of corm-like growths 

 were found attached to the roots, and not to under- 

 ground stems. These growths were of all sizes up to three- 

 fourths of an inch in diameter and irregularly rounded. No in- 

 dications of buds were discovered. Some of the largest corms 

 were planted, but did not grow. Le Maout and Decaisne mention 

 a Nephrodium esculentum of Nepaul, that furnishes edible tubers, 

 used by the natives. 



It would hardly seem that the economy of this sworn fern 

 requires a third means of reproduction, since it sends out numer- 

 ous runners and also produces spores freely. — Mrs. J. M. Mil- 

 ligan, Jacksonville, III. 



[In Jenman's synoptical list of the ferns of Jamaica, pub- 

 lished in the Bulletin of the Botanical Department of Jamaica, 

 the writer notes that this tuber-bearing habit is characteristic of 

 several species of Nephrolepis. Among the points which dis- 

 tinguish N. pectinata from the others, the absence of tubers is 

 mentioned, wliile in another species these are so common that 

 Hooker named it N. tuberosa. The tubers are considered as a 

 third means of propagation, the other two being spores and 

 stolons. As our correspondent notes, the common sword fern 

 {N. exaltatd), has all three. In Jamaica, this species often 

 ascends the trunks of palms to a considerable height by means of 

 its stolons, from which it is commonly called the walking-fern in 

 Jamaica. Can our readers furnish us with other instances of 

 ferns bearing tubers ? — Ed.] 



FERN VARIATION. 



IN reference to the incised varieties of Dryopteris acrostichoides 

 and Asplenium Trlc/iomanes y WLr. Raynal Dodge explains the 

 peculiarity as resulting from the removal of the forest trees 

 in whose shade the plants grew. If these peculiar forms are en- 

 titled to be termed varieties, why may not the same peculiarity 

 in Osmunda cinnamonea be entitled to the same dignity. I have 

 found a large quantity of fronds of the last named fern very 

 beautifully incised, as much so as any fern I ever saw. I think 

 they may properly be labeled 0. cinnamomea incisa. 



