1869.] -*■"-'■ [Wood. 



brown, rarely subtransparent at the apex ; cytioplasm colorless, granu- 

 lar, often extending out beyond the sheaths, generally articulate ; joints 

 longer or shorter than broad ; sheaths close, thick, brownish olive or yel- 

 lowish brown, for the most part truncate at their ends and open, their 

 surface sometimes irregular ; heterocysts subquadrate, single, interstitial. 

 Diam. trich. cum vag. y/oo^-y/o^" j I'am. c. v. jzos"—7^W- 

 Hab. South Carolina, in ramis Celtis. Prof. H. W. Ravenel. 



GEN. SYMPHOSIPHON. 



S. CORIACEA. Sp. Nov. 



S. in strato ad 2 lineam crasso, coriaceo, nonnihil spongioso disposita ; 

 trichomatibus pseudoramuli.sque flexuosis, dense intricatis, arete concretis ; 

 trichomatibus internis rarissime hand articulatis sed plerumque breve et 

 distincte articulatis, plerumque pallescentibus, interdum dilutissime 

 aerugineis, saepe interrviptis ; articulis granulosis, interdum sejunctis, 

 diametro subaequalibus ad fere duplo longioribus ; vaginis crassissimis, 

 distincte lamellosis, achrois et coloris expertibus, stratis externis saepe 

 intumescentibus, superficie conugata, hirta ; cellulis perdurantibus 

 nullis ? 



S. Forming a leathery and spongy, tough stratum of about 2 lines in 

 thickness and of a light slate color. Filaments and branches flexuous 

 densely intricate, closely concreted ; internal filament very rarely not 

 articulated, in most cases very distinctly jointed, generally nearly 

 colorless, sometimes with a faint aeruginous tint, often interrupted ; 

 articles granular, sometimes disjoined, from about equal to twice the 

 length of their diameter ; sheaths very thick, transparent and colorless, 

 very distinctly lamellated, external lamella often swollen, their surface 

 corrugate and variously rough and ragged ; heterocysts none. ? 



Diam. trich. c. vag. max. i2L¥(t"=-00083 ; sin. vag. max. 12000"= 

 , 00025. 



Remarks. — I have examined a great number of filaments and have 

 nowhere seen anything like a heterocyst. The specimens examined had 

 been preserved in solution of acetate of alumina, but I do not think the 

 salt had changed materially their color. 



Hab. Texas. Prof. Ravenel. 



GEN. TOLYPOTHRIX. 

 T. DiSTORTA. [MulUr .) Ktz. Var. f 



In aquario. Dr. Fricke. 



Remarks. — The specimens which have been identified as T. distorta, 

 agree well with the descriptions of that species, except in the fact that the 

 heterocysts are often 4-seriate and that they are rather parallelogram- 

 matic than subglobose, as well as in the circumstance that the sheaths 

 are close. I do not think the differences are sufficient to distinguish 

 species. 



