OF THE FILAMENTOUS ALGAL 
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CHAPTER YII. 
OF THE FILAMENTOUS ALG^E. 
Although there are many more filamentous Algas than 
those indicated below, yet for the purposes of the collector 
we prefer to group together only the families of Confer- 
vacese, Zygnemacese, and (Edogoniacese. All these, with 
few exceptions, inhabit the same localities ; in many respects 
are very similar to each other ; and are prepared for the 
herbarium in the same way. To these may be added 
also the genera Batrachospermum, Ulothrix (a portion only), 
Yaucheria, Hydrodictyon, Calothrix, Tolypothrix, and Hy- 
drurus. 
Almost all the members of this group are partial to 
standing water, swamps, bog-holes, and lilliputian bays, in 
streams and ponds. The species of Zygnema are found 
in clear cold springs, which they sometimes fill with their 
glossy green tufts. On the other hand, Cladophora, Ulo- 
thrix, and Yaucheria take up their abode in rivulets and 
watercourses, where they attach themselves to stones and 
other fixed objects, and thus safely anchored, let their 
long wavy filaments follow each motion of the stream. 
Eor specimens of Zygogonium, Hormidium, Schizogonium, 
Chroolepus, and some of the Yaucherise, the collector 
must search, not the water, but the land-damp stones and 
muddy ground, so that in their mode of life they are 
exceptions to the great bulk of the filamentous Algse : 
as are also the genera Chantransia, Microthamnium, Gon- 
grosira, Chlorotylium, Coleochsete, and Chaetophora, which, 
m account of their habit of forming close matted strata, 
must be excluded from our ‘filamentous group,’ and be 
treated -of elsewhere. 
