THE ALGAE 



179 



TRICHOGYNE 



CARPOGONIUM 



c 



Fig. 171. — Corallina officinalis. A, Longitudinal section of a female conceptacle with 

 young procarps. B and C, Young procarps with carpogonia. {After Sumeson.) 



At this stage the auxihary cell of this procarp branch fuses with the 

 auxiliary- cells of the neighbouring procarp branches until finally a single large 

 central cell is produced from the union of auxiliary cells. The diploid zygote 

 nucleus now migrates into the central cell, which thus contains many mono- 

 ploid nuclei from the auxiliary cells which have contributed to its formation 



