473 



Beginning from the base, the stalk consists in the normally 

 developed antheridial stands of two cells (Fig 430 b); the lower- 

 most about 12 ;j. long and 20 // broad is nearly immersed in the 

 tissue of the branchlet, the uppermost about 12 16 // long and 

 24 fji broad has rather thick walls. The antheridial part is nearly 

 cylindrical; it is terminated by a sterile part. This consists in 

 the different spe- 

 cimens of a va- 

 rying number of 

 short cells, two to 

 five, or sometimes 

 it terminates in a 

 longer tricho thai- 

 lie prolongation 

 (Fig 430 ). A few 

 times I have found 

 ramified antheri- 

 dial stands where, 

 in two cases, a 

 smaller fructife- 

 rous branch issued 

 from the second 



cell in the Stalk 

 Fin- 



and in another 



Fig. 430. Herposiphonia tenella (Ag.) Nagl. a, part 

 ^ a ms ^ e pl an ^ b, transverse section of antheridial 

 stand, c, apex of branchlet with antheridial stand 

 from the third basal cell of which a sterile well devel- 

 P ed trichoblastic branch is given off. (a. about 



50:1; b and c, about 200:1.) 

 were developed in 



the stalk, and from the uppermost of these cells a well developed, 

 ramified, trichoblastic, sterile branch issued (Fig. 430 c). This shows 

 that in this species there is a tendency not to use the whole tricho- 

 blast in the formation of the antheridial stands, this feature, as men- 

 tioned above, being in most cases confined to a few sterile cells 

 in the upper end of the antheridial stands, in others to a shorter 

 or longer hairlike prolongation, rarely to a whole ramified tri- 

 choblastic branchlet. The whole antheridial stand is generally much 

 curved in this species in contradistinction to the straight ones 

 in H. secunda. And while the antheridial stands, rarely more than 

 four, are crowded together in the upper end of the branchlets 

 in H. secunda, these, in H. tenella (up to a number of ten upon 



