122 



THE BOTANICAL MAGAZINE. 



IV<a. XXXV. No. 415. 



>t-»- 



the . preceding species, because 

 leaves are arranged in % clock- 

 wise man ner. Foliar traces, two 

 in number, depart from both sides 

 of a gap (Fig. 4, A ; marked ^ 

 with X ). 



Polystichum varium (L.) Pr. 

 Oblique or erect rhizome with 

 leaves arranged very closely in -/s 

 clockwise manner. The stelar con- 

 struction is quite similar to that 

 of the above mentioned species. 

 The number of foliar traces is five B 

 to seven, one departing from the 

 bottom, the others from both 

 sides of a gap. The last pair is 

 always larger than the others 

 (Fig. 4, A ; marked with o). 



Polystichum Standishii 



(Moore) Chr. Erect rhizome 

 with -/s counterclockwise foliar 

 arrangement. The stelar struc- 

 ture is quite contrariwise to the preceding 

 five to seven in number. 



.,^^-:r.-s"«t;t'.-: 



C:^-^- 



Fig. IV. Developing figures of 

 steles with f clockwise (A) or counter- 

 clockwise (B) phyllotaxy. The depart- 

 ing points of foliar traces are also 

 marked (details in text). 



Foliar traces are from 



General Considerations and Conclusions. 



The gaps of the stele above described, have the relation to foliar 

 traces. The foliar traces depart from the margin of gaps as one, 

 two, three or more separate strands according to different species. 

 In his paper advocating his view of the absence of foliar gaps in 

 Lj'copsida, Jeffrey^- characterized the foliar gap in the Ibllowing 

 manner : "the foliar gap may be distinguished from the other gaps 

 in the wall of the fibrovascular hollow" cylinder by the fact that it 

 occurs immediately above a leaf trace. A true foliar gap, moreover, 

 is always related to put a single leaf-trace. If several traces appear 

 in relation to a stelar gap and especially if they are related to the 

 side of the gaps, it may be concluded at once that no true foliar 

 gap is present." Following this restriction the gaps of Polypodiaceous 



1) Jeffrey, E. C. (1908) Are there foliar gaps in Lycopsida? — Bot. Gaz., Vol. 

 46, p. 242. 



