(7) 



abundantly, but always barren, often scarcely exceeding half an inch in 

 size, but as much branched almost as specimens measuring a foot in 

 diameter. 



EXPLANATION OF PLATE LXVIIL 



Fig. 1. — Plocamimn coccineum, natural size. 

 2. — Branch witli stichidia. 

 3. — Stichidium from same. 

 4. — Tetraspores from same. 

 5. — Brancli with tubercle. 

 6. — Spores from same. All magnified. 



