IGO CRYPTONEMIACEJE. v. 



VIII. CoNSTANxniTEA. Frond caulescent, branched ; the branches expanding into 

 carnoso-coriaceous definite lamina. 



Tribe 3. Eu-GiGAHXiNEiE : Frond cartilaginous, wholly composed of innumerable, 

 slender, anastomosing, longitudinal and horizontal filaments, set in a firm, 

 pellucid gelatine. Tetraspores collected in sori. 



* Nucleus lodged ivithin a pseudo-pericarp, composed of densely interwoven filaments. 



IX. GiGARTiNA. Frond terete or flat, mostly branched. Conceptacles external, 

 globose. 



X. iRiDiEA. Frond flat, simple or vaguely cleft. Nuclei immersed in the frond. 



** Nucleus immersed in the frond., icithout definite border. 

 XL Chondeus. Frond dichotomous, flabelliform. 



Tribe 4. Endocladie^: i^roni cartilaginous, terete, sub-tubular, formed of a soli- 

 tary, longitudinal, articulated, axial filament, from which short, horizontal, 

 fastigiate filaments issue on all sides, and are united by firm gelatine into a 

 continuous peripheric stratum. 



XII. Endocladia. Peripheric filaments whorled. 



XIII. Gloiopeltis. Peripheric filaments alternate. 



Sdb-order 2. CRYPTONEME^. Nucleus simi^le ; consisting of a single round- 

 ish mass of spores. 



Tribe 5. Gastrocarpe^ : Frond membranaceous or sub-gelatinous ; its inner 

 stratum (sometimes obsolete in the tubular fronds) composed of elongated 

 filaments variously anastomosing ; its outer stratum of one or more rows of 

 roundish-polj'gonal cells, smaller towards the surface, and coalescing into a 

 membranous cortical layer. 



* Frond rigidly nwmbranaceous, flat and leaf-like. 



XIV. Cryptonemia. 



Frond either filiform or flat, very lax within, or sometimes tubular and inflated. 



t Conceptacles external with a definite pericarp. 



AV, Chtlocladia. Conceptacles external, sessile, conico-acuminate, containing a 

 mass of spores surrounded by a gelatinous Ihnbus. Frond tubular, linear. 



