SYNOPSIS OF THE ORDERS OF CHLOROSPERME^E. 
1. SiPHONEiE. Rooting or basifixed. Frond simple or compound, formed either of a 
single, filiform, branching cell, or of many such cells united together in a spongy 
frond. (Marine or fresh-water.) 
2. Dasycladeae. Rooting. Fronds consisting of a simple or branched inarticulate 
axial thread, whorled with articulated ramelli. Spores spherical, developed in 
proper fruit-cells. (Marine.) 
3. ValoniacEjE. Rooting. Fronds polymorphous, formed of large vesicated cells, 
filled with watery endochrome. (Marine.) 
4. Ulvaceae. Basifixed. Fronds tubular or flat, membranous, formed of minute 
quadrate cells. ( Marine or in fresh water.) 
5. B A t R A c H o s ? E r M E 7E . Basifixed. Fronds filiform ; the axis inarticulate, composed 
of minute cylindrical or polygonal cells, naked, or whorled with articulated ramelli. 
Spores in moniliform strings, naked. {In fresh water.) 
6. Confervaceae. Basifixed or floating. Fronds filamentous, articulated. Endo- 
chrome diffused. Zoospores minute, formed in all the cells. (Marine or in fresh 
water.) 
7. Zygnemaceas. Floating. Fronds filamentous, articulated. Endochrome of some 
definite figure. Zoospores large, formed by the union of two endochromes (of 
different cells), or by the bisection of a single endochrome. (In fresh water.) 
8. Hydrodictye^e. Floating. Frond forming a net-work with polygonal meshes ; 
each side of the mesh formed of a single cell. Viviparous. (In fresh water.) 
9. OscillatoriacevE. Basifixed or free. Frond formed of subsimple filaments, having 
a membranous inarticulate tubular sheath, enclosing an annulated medulla, 
composed of very short, lenticular, cellules. 
10. Nostochineas. Basifixed or free. Fronds consisting of moniliform jelly-coated 
threads, free or enclosed in a gelatinous matrix. 
11. Desmidiaceae.* Microscopic, unicellular, green; wall of the cell membranous: 
growth by semisection of the cell, and the evolutions of two new half-cells at 
the medial line. 
12. Diatomaceae.* Microscopic, unicellular, yellow-brown ; wall of the cell silicious : 
growth and fructification as in the preceding Order. 
13. P almellaceae. Cells globose, or ellipsoidal, free, or lying in a gelatinous matrix, 
not forming either threads or membranes. Propagation by division of the 
endochrome. 
* These Orders are not included in the present work. The North American species have been ably worked 
out by the late Professor J. W. Bailey of Westpoint, whose numerous memoirs on the subject have a world- 
wide reputation. The species are all of microscopic size, and some of them, from their extreme minuteness, 
and the delicate sculpturing on their cell walls, form admirable test-objects for microscopes. 
