ANIMAL-PLANTS AND SEA-WEEDS 113 



the branches, but, instead of being membranous in 

 texture, the branches are constructed of an exceed- 

 ingly beautiful ivory coralline substance. The 

 example in Fig. 73 reverts again to the mem- 



Fig. 73. Animal-plant cells arranged after the manner 

 of a leaf, instead of branches 



branous structure, but with an entirely different 

 cellular arrangement. Instead of forming branches, 

 a leaf or frond-like arrangement is assumed. The 

 cells are packed and crowded together on each side 

 of the leafy organisms, which are familiar to seaside 

 visitors as "sea-mats." Specimens of the natural 

 size were the broader fronds in Fig. 70, the 

 branch-like and finer kinds beine similar to that 



