272 Harsh berger : Water-storing tubers 



Nephrolepis, called by her N. exaltata, while changing the fern 

 from one pot to another. The tubers, she says, were of all sizes 

 up to three fourths of an inch in diameter and irregularly rounded. 

 No indications of buds were discovered and some of the largest 

 tubers were planted, but did not grow. 



In all probability, as pointed out by J. Birkenhead,* the fern 

 described by Mrs. Milligan as N. exaltata was N. cordifolia (= N. 

 iubcrosa). Nephrolepis philippinensis produces tubers in profusion, 

 so also do N. Pluma var. Bausei and N. undulata, all deciduous 

 ferns. A peculiar feature of these deciduous ferns, Birkenhead 

 states, is that the plant of one season does not always grow again 

 from the old caudex, but there is in many cases a tuber formed 

 close to the old caudex, from which growth commences in due 

 course the following season. The other tubers formed at various 

 distances away from the main stem also commence growth and 

 produce plants. One of the points which distinguish N. pectinata 

 from the others, as Clute adds editorially in commenting on 

 Birkenhead's article, is the absence of tubers. Adiantum dia- 

 phanum {A. setnlosuni) produces tiny tubers on its roots, the size 

 of mustard seeds, some roots bearing twenty to thirty tubers in a 

 length of three to four inches. Velenovsky f in his Vergleichende 

 Morphologie der Pflanzen also describes the tubers of Nephrolepis 

 cordifolia ( = N. tuberosd). 



Le Maout and Decaisne mention Nephrodium escidentumX ot 

 Nepaul that furnishes edible tubers used by the natives. Hein- 

 richer, § in a paper published since the above statements were 

 written by me, has presented a complete study of the regeneration 

 of several species of Nephrolepis from the fleshy tubers noticed 

 above, when these are cut and experimentally treated. He finds that 

 tubers are formed on N cordifolia Presl ( = N. tuberosa Presl), 

 N. hirsutula (Forst.) Presl, N. Pluma Moore, and N. philippinensis 



Hort. 



N. cordifoli 



* Birkenhead, J. Tubers of Nephrolepis. Fern Bulletin 7 : 35. 1899- 



t Velenovsky, J. Vergleichende Morphologie der Pflanzen, Teil L P ra S 



1905. 



t I cannot find this name, but give it as a quotation. 



\ IIkinricher, E. Zur Kenntnis der Farngattung Nephrolepis. Flora 97; 

 43-73- & 1,2. 28 D 1906. N. Pluma Moore is considered a variety of A- 



cordifolia. 



