vin 



MARATTIALES 



289 



The Adult Sporophyte 



According to Holle (1. c. p. 218) the four-sided apical cell 

 found in the stem of the young sporophyte of Marattia is re- 

 tained permanently, but in Angiopteris this is not the case, as 

 in the older sporophyte a single apical cell is not certainly to be 

 made out. Bower ((11) p. 324) comes to the same conclusion 



Fig. 161. — A, Section of the stipe of Angiopteris evecta, natural size; B, section of the 

 rachis of the ultimate division of the leaf of Marattia alata, Xis; m, mucilage 

 duCL's; C, collenchyma from the hypodermal layer of the rachis, X250; D, part 

 of the vascular bundle of U, X250; t, tannin cells. 



as Holle, although in an earlier paper (2) he attributes a single 

 apical cell to the stem of Angiopteris. The stem in both genera 

 becomes very massive, but its surface is completely covered by, 

 the persistent stipules. 



The structure of the stem in Angiopteris has recently been 

 carefully investigated by Miss Shove ( i ) who has also reviewed 

 19 



