KEY TO THE HIGHER ALG OF THE ATLANTIC COAST. 
a short, cylindrical, solid; margin of frond wavy or rufiled; 
ery lar, 
re. . ; í $ ‘ 
Tufts spines tik densely i interwoven.’ eo ee a. 
AMER. NATURALIST, VOL. 26 
401 
a, Pine flat, winged; trong ay Tigh ow. 1 
a. Stipe short, flattened; much smaller ne more cliente ena the 
preceding huge “‘ oar-weeds ” and “ 18 
b. Stipe nearly round, 1 to 6 feet ee © COMMON: 4 i A 15 
b. ipe flat, 3 to 4 inches long; rare é meshes tak T 
c. Frond pinnatifid us with veiness teaflela. Pee es aaa 
d. Rocks, etc., below low tide; nN. PRAE eee eae 
e. Frond Goustricted a ee: i ne 2 feet onde go eee Oe Vga 
©; Frond not constricted, 1 to 40 feetlong. . . . ......22 
f. Adhering strongly to paper; oS . 24 
g. On s, Fucus, Chordaria, etc.; c o: : ib ele rane 5° 
h. Fruit— groups of spores in transverse lines. . . » .. . - 26 
i, Frond tapering each way; 1to4lines wide. e ..... . 27 
i. Frond an inch or more wide. . mre Shae 
$ Dark green; attenuate te bape. o SO ee oe 
j. Pale; abruptly tapering to bas Se neers evn ee 
k. Fruit — minute, scattered dot- like sori. . Vier Races rae E 
l. Frond with long, filiform, sub-simple biek E a l 
l. Irregularly, mostly dichotomously branched. . . . . . . + 32 
m. Slender, with a few short ip Ol LORT ikke a ee OO 
m. Clumsy with long worm-like Mea eer ira aa 
m, Filiform; branches long; dint sts asw ide. 
n. On Cor graiia, etc.; tuber size of a walnut. or rei becoming 
finally hollow . 36 
0. Brown pencil- like tufts on oa common ee hae rr trey | 
P. Several species probably here; the common . . 38 
q. Branches slender; branchlets forked, sage se Wisi: EN SO 
q. Coarser, branchlets simple, irregularly whorled. . . . . . . 40 
T. In globose tufts on small Algæ. . . > eow sick Ae 
r. In ee patches on rocks ag BbnOs Gon eee ee are eae 
‘8. es mostly "o erie obte A Os a e 
8. Canepa mostly altern u 
t, Propagula (pod-like bodies ETIE as ake PEA P A TE which 
are formed by partial or entire transformation of a branch 
elliptical, sessile. fates ae 
t. Propagula forming swenmgs m the — biaha” ee ae 
u. Joints of stem decidedly longer than broad. . .- ++ +++ W 
u. Joints of stem not longer than broad. v 
V. Zigzag, much forked; small spine-like S at nearly etery 
joint. . 51 
V. Stem ex current;  propagite ‘elliptical; branche e a kp 
ve rr elongated; our commonest - 44 
+ Lropagula linear, tipped with aan eat a the dinno 
branchle - 45 
Ww. 
