226 Chaetophoraceae 



Thallus microscopic, growing within the membrane of other 

 algae, irregularly branched. Cell-division is mostly confined to 

 the pointed end cells. Chromatophore a sheet covering most of 

 the cell-wall, inclosing a pyrenoid. 



Four to eight zoospores may be formed in any cell and escape 

 by a round hole through the cell-wall and host plant ; they lack 

 a red eye-spot, the number of cilia and manner of germination is 

 unknown. 



Inhabitants of salt water, for the most part. Type, E. viridis 

 (Reinke) Lagerh. [Etym. ivoov, within, and dipiia, cuticle.] 



Hansgirg ('89), believing that the type species Endoderma viridis 

 was identical with Periplegmatium ceramii Kutz., transferred the 

 several species of Endoderma to Periplegmatium. Kiitzing's type, 

 besides having, so far as can be judged from his published figures, 

 a different type of branching from that seen in Endoderma viridis, is 

 described as epiphytic on Florideae while Endoderma is endophytic. 



Hansgirg's attempt does not seem to have been taken very 

 seriously, and reliance has been placed in the judgment of Profes- 

 sor Wille ('90) that Endoderma is to be retained. 



1. Endoderma Wittrockii (Wille) Lagerheim, Ofvers. Vet. 

 Akad. Forhand. 1883 2 : 75. 1883. DeToni, Syll. Alg. 1: 209. 

 1889. Wille; Engler & Prantl, Nat. Pflanzenfam. I 2 : 94. /. 57. 

 1890. 



Entocladia Wittrockii Wille, Forhand. Vidensk. Selskab. 

 Christ. 1880 i : 1-4. //. 1880; Jahrb. wiss. Bot. 18: 435-437. 

 //. 16. f. 12-14. 1887. Hauck ; Rabenh. Krypt. Flor. Deutsch. 

 2:463./. 199. 1885. Collins, Bull. Torrey Club, 18 : 340. 1891. 



Periplegmatium Wittrockii Hansg. Flora, 72 : 59. 1889; Phys. 

 und Phyc. Untersuch. 240. 1893. Mobius, Notarisia, 6 : 1291. 

 1891. 



Plant a simple or irregularly branched filament, tapering at 

 the ends, sometimes forming a small single-layered plate by reason 

 of the partial coalescence of the branches ; cells 5-1 o/jl in diameter, 

 and y-12/i long (pi. 42, f. 1). 



Exsic. : Phyc. Bor. Am. 265, Nahant, Mass. June, 1893 (F. 

 S. Collins). Endophytic between the layers of the cell-wall of 

 Elachista fucicola. 



Massachusetts : Nahant, July (452). 



Connecticut: Madison, July, August (453). 



