NEMALIOXACEAE. 511 



The filaments are usually only a line long or less. Under a compound micro- 

 scope they are seen to be unbranched and to consist commonly of a single row 

 of cells, which are mostly about as broad as long. In older conditions the 

 filaments may become more than one cell broad. 



Family NEMALIONACEAE. 



Acrochaetium crassipes Befrg. This species was originally described from 

 the Danish West Indies. It is a very minute plant, only a few cells high, with 

 a few branches 1-6 cells long. It occurs as a microscopic epiphyte on Centro- 

 ceras clavvlatum at St. David's Island. (Phye. Bor.-Am. 2033.) 



Acrochaetium infestans Howe & Iloyt, is a microscopic filamentous plant, 

 of which the vegetative parts are chiefly emlozoic, creeping in the gelatinous or 

 chitinous stalks and stolons of hydroids and of filamentous bryozoa. The 

 interior filaments are freely and irregularly branched, usually in a loose ram- 

 bling intricate fashion, but occasionally forming a sort of pseudoparenchyma 

 with shorter, more compacted cells. The monosporangia are borne on external 

 filaments, which are commonly very short and few-celled, simple or with a few 

 short branches, or occasionally reduced to a single exserted monosporangium. 

 [Phyc. Bor.-Am. 2194, as Ehodochorton membranaceum.] 



Acrochaetium (Chantransia) is a genus of small, filamentous, chiefly epi- 

 phytic, endophytic, epizoic, or endozoic red algae. It is doubtless represented 

 in Bermuda by several other species, the determination of which awaits critical 

 study. One of these, in and on Dudresnaya crassa, has been distributed by 

 Collins as Chantransia corymbifera Thuret* (Phyc. Bor.-Am. 1880.) 



Trichogloea Herveyi Setchell (Phyc. Bor.-Am. 2034) is a more or less cal- 

 cified, very lubricous, irregularly branched plant, reaching a length of four or 

 five inches. No diagnosis of the species has been published up to the date of 

 writing. It occurs at or below low-water mark, as at Cooper 's Island. 

 Endemic. 



Helminthocladia Calvadosii (Lamour.) Setchell, more commonly known 

 as Helmintliocladia purpurea (Harv.) J. Ag., appears to occur in the spring 

 months at Long Bird Island (Collins, Phyc. Bor.-Am. 2035) and at Bailey's 

 Bay (Wadsworth). Though not calcified, it is rather firmer in texture and a 

 little less lubricous than the Trichogloea Herveyi and is more brownish red or 

 greenish red (less pink) in color. The Bermuda plant differs somewhat in 

 habit from the European, but in other respects seems to offer little or nothing 

 to distinguish it. 



Liagora valida Harv. grows on surf-swept rocks between the tide lines, as 

 at Hungry Bay, Cox's Bay, Achilles Bay, and St. David's Island. In this 



* To a French plant, hemi-endophytic in Helminthocladia Calvadosii and de- 

 scribed and figured by Bornet and Thuret under the name Chantransia corymbifera 

 Thuret, the Bermudian plant in Dudresnaya bears considerable resemblance. How- 

 ever, the original description of C. enrinnMfrra apparently confused two species, 

 though only one of them, an epiphyte on Ceramiinn ntbruni, was actually cited. 

 This epiphyte on Ceramium, which has been renamed [Chantransia Thurctii (Bornet) 

 Kylin], should manifestly be considered the type of Cliantninsiii corymbifera Thuret. 



