1914] Mccormick— symphyogy n a aspera 405 



strands in Pallavicinia, Hymenophyton, and Symphyogyna, and they 

 have demonstrated with eosin that in Pallavicinia Lyellii the 

 strands conduct water. Their detailed drawing of part of a cell 

 showing pores (pi. i.fig.4) is representative of the pores in Symphy- 

 ogyna, with the probable exception that in S. aspera the pores are 

 more regularly arranged and more obliquely spiral. Sections of the 

 thallus treated with acidulated alcohol and stained with methylene 

 blue, following Mayer's method given by Haas and Hill (19), 

 gave the test for pectose by showing the middle lamella stained a 

 deeper blue (fig. n). The pores are so narrow that except in very 

 thin sections they are readily overlooked in transverse sections. 



In the species of Symphyogyna which he examined, Leitgeb 

 found the dolabrate apical cell like that in Pallavicinia, etc., though 

 for S. sinuata he makes the statement that at first glance one 

 might think the apical cell like that in Pellia calycina, Blasia, etc., 

 which is the well known wedge-shaped cell. . However, he con- 

 siders that such a view is an erroneous one, and that the apical cells 

 of all the species of Symphyogyna are alike. S. aspera has two 

 types of apical cell, the dolabrate and the wedge. Stephani 

 identified the species and grateful acknowledgments are due him. 

 However, in the material sent to him, the part collected at Texolo, 

 Mexico has the wedge-shaped apical cell, and that collected at 

 Xalapa has the dolabrate apical cell. Moreover, the thallus of the 

 material collected at Texolo is slightly broader and less deeply lobed 

 than the material collected at Xalapa. The last two characters 

 may be overlooked as due to a difference in environment; but 

 when to them is added a difference in the apical cell, one may be 

 justified in considering the material as representing different species, 

 especially since species are often separated for less convincing rea- 

 sons. If both forms belong to the same species, then there is the 

 interesting situation of two types of apical cell in mature plants of 

 the same species (figs. 12-16). However, Campbell (3) reports 

 two types of apical cell in Calycalaria radiculosa. 



In the dolabrate cell a segment is cut off alternately to the right 

 and left. The primary segments on both sides are divided longi- 

 tudinally, and from the middle secondary segment in each side can 

 be traced the one-layered winglike extensions of the thallus (fig. 17). 



