Myxophyceae 225 



like coating on the rocks below the great cataract. Niagara Falls. (Wood). 

 Dark brown coating on wet rocks. Niagara. (Wolle). Rhode Island. 



New Providence. (Bennett). Connecticut. Forming dark brownish 



patches on submerged limestone rocks. Twin Lakes, Salisbury. August, 

 October 1892. (Holden). Growing on outside of Unio shells. Twin Lakes, 

 Salisbury, Litchfield County. August 1895. (Setchell and Holden). New 

 Jersey. On rocky shores of Morris Pond. (Wolle). On moist ground. 

 Closter, Bergen. (Austin). Pennsylvania. Moist ground in extended 

 patches and on dripping rocks. (Wolle). North Carolina. Moist ground. 

 (Ravenel). Iowa. Fayette. 1905. (Fink). Colorado. Wet rocks. (Bran- 

 degee). Bermudas. (Farlow). 



413. Scytonema badium Wolle. Fresh Water Algae. III. Bull. Torr. Bot. 



Club. 6: 184. 1877. De Toni. Syll. Algar. 5: 524. 1907. 



Plant mass thin, brown (b a d i u s) ; filaments 40-75 mic. in diame- 

 ter, somewhat erect, appressed, short; false branches flaccid, divari- 

 cate, single or in pairs; sheaths wide, yellowish olive; trichomes 2-2.5 mic 

 in diameter, sometimes continuous, sometimes showing distinct transverse 

 walls; cells about as long as wide; heterocysts scattered or situated at the 

 base, somewhat spherical or oblong; cell contents pale blue-green. 



New York. On old wood. Herkimer County. (Austin). 



414. Scytonema fuliginosum Tilden. American Algae. Cent. VII. Fasc. i. 



no. 629. 1909. 



Plate XIII. fig. 7, 8. 



Plant mass thin, bluish green; filaments 28-50 mic. in diameter; sheaths 

 folded into many layers or laminations; layers much dilated, dark brown 

 in thicker parts; trichomes 10-20 mic. in diameter; cells 1.4-5 rnic. in length; 

 heterocysts 12-16 mic. in diameter, spherical, oval or somewhat quadrate; 

 cell contents gray green. 



Hawaii. Forming a thin layer on bottom of small shallow tide pool 

 just below high tide. Pahala Plantation beach, south shore of Hawaii. 

 July 1900. (Tilden). 



415. Scytonema alatum (Carmichael) Borzi. Morfologia e Biologia delle 



Alghe Ficocromacee. Nuovo Giorn. Bot. Ital. 11: 373- i879- Bornet 



and Flahault. Revis. des Nostoc. Ann. Sci. Nat. Bot. VII. 5: no. 



1887. De Toni. Syll. Algar. 5: 528. 1907. 



Harvey. Nereis Boreali-Americana. Part III. 99. pi. 48- A. f. 1-4. 1858. 



(Petalonema alatum Berk.). Wood. Contr. Hist. Fresh-Water 



Algae North America. 66. 1872. Wolle. Fresh-Water Algae U. S. 267. pi. 



188. f. IS, 16. 1887. Setchell. Notes on Cyanophyceae. — II. Erythea. 4: 



193. 1896. Hone. Petalonema alatum in Minnesota. Minn. Bot. Studies. 



3- 47- Pl- 13. 1903. 



Plate XIII. fig. 9- 

 Plant mass caespitose, mucous, black or brown; 24-66 mic. in diame- 

 ter, 4-8 mm. in length, flexuous, erect or appressed; false branches short, 

 spreading, irregular in outline; sheaths forming lamellose wings or mem- 



