50 



and Chylocladia . 



During these changes, the large nucleus of the aux- 

 iliary cell continues to increase in six.e. It becomes al- 

 most empty of contents, the nuclear outline "becoming less 

 and less distinct, and finally the nucleus disappears in 

 the cytoplasm (fig. 91), 



Changes also take place in the other elements of the 

 young cystocarp. The central cell, which at first contains 

 a large central vacuole, "becomes filled with homogeneous cy^ 

 toplasm with numerous nuclei formed "by the multiplication 

 of those originally present (fig. o7), Prom the Hides of 

 tlie basal cell of the procpjr'p soon after fertilization sev- 

 eral sina.ll cells are cut off successively'' (fig. 91). 

 These in turn divide, ^xid tiie outer cell becomes an invol- 



i;cral ray (f igs.87,?/) , Three to seven involucral rays are 

 formed; they are of various six-es and ages, and curve up 

 over t}.e cystocarp so fc,s to cover it almost completely, ex- 

 cept e.t the top. The structm^e of tlie involucral rays of- 

 fers nothing especially remi.,rkable . They are distended 

 sacs, pe-le pink in color ov/ing to the presence of a small 

 number of cliroma.tophores, A tliiTi layer of protoplasm 

 bounds a very large vacuole. The nuclei may become quite 



numerous, 07 having been counted in a ray of average size. 



