604 MINNESOTA BOTANICAL STUDIES. 



than elsewhere, more deeply colored and possesses a glossy 

 smoothness. 



The cystocarps sometimes appear as surface elevations 

 though commonly they are developed in the marginal and sur- 

 face proliferations. They are most numerous and attain 

 greatest size in the marginal area while at the center they are 

 scattering and poorly developed, numbering from 8 to 10 per 

 sq. cm. as compared with 15 to 18 near the margin. 



^The broad flat branches of the lamina, owing to extreme 

 thinness and position, bear few cystocarps though the number of 

 proliferations may be great. 



The epidermal cells of the lamina are very similar in every 

 respect to those of the stipe except that the arrangement is less 

 compact. The same may be said regarding the pseudo-cortical 

 area, but a difference is seen in the pseudo-medullary cells ; 

 these are all filamentous, densely rilled with granular proto- 

 plasmic contents (PI. 42, Figs. 6 and 7) and so joined as to form 

 a complete network. 



Through the use of certain staining reagents it was found that 

 a protoplasmic connection existed between the several cells of 

 the frond, best seen in the pseudo-medullary region of the 

 lamina. (PI. 42, Fig. 8.) On further examination, using alco- 

 holic solution of fuchsin as a staining reagent, protoplasmic 

 pits were seen to exist between the several cells. These pits 

 were composed in every case of two minute callous plates which 

 when stained were found to give a reaction similar to that of pro- 

 toplasm. It was not possible to determine the function of these 

 connections, but no doubt they serve as paths of communication 

 between cells. In Schmitz's discussion of the protoplasmic 

 pits he shows that they are traversed by plasma-cords which 

 serve for conduction of dynamic influences from cell to cell. 

 He believes a transfer of dissolved food material possible be- 

 cause of the pores in the pit, but does not regard as probable 

 the transfer of protoplasm. 



Proliferations and cystocarp. PI. 42, Fig. 9, represents an 

 early stage in the development of a proliferation. Certain of 

 the epidermal cells become slightly modified in shape, cell di- 

 vision takes place vertically and apparently transversely. This 

 increase in the number of cells causes an elevation to develop 

 and as it continues a well-developed proliferation eventually pre- 

 vails which may or may not bear a cystocarp. 



