1895.] On Costaria. 57 
The other species, Costaria Turnert Grev., was named Fu- 
cus costatus by Turner in 1819, * but Greville in 1830 changed 
it to Costaria Turneri Grev.* 
Under the present rules of nomenclature we must then re- 
turn to Turner’s specific name which results in Costarza cos- 
tata (Turn.). 
Since the two species have been somewhat confused and 
the genus will have to be broadened somewhat to include the 
new species, the following synopsis may not be amiss. 
© some it may seem that the possession of a single broad 
rib ought to be considered as a generic distinction, but after 
a careful comparative study of the structure of this plant with 
Costaria Mertensit J. Ag., I prefer to broaden the generic 
description enough to include this plant 
COSTARIA, Greville. Alg. Brit., Syn. p. XXXIX. 1830. 
Plant undivided, one to five-ribbed; ribs when more than 
one, radiating from a simple, plain stipe. Fruit as in Lam- 
inaria, indefinite brown spots on any part of the plant. 
§I. Plant 5-ribbed. 
COSTARIA MERTENSII, J. Ag. Spec. gen. et ordin. Alg. 
1: 140. 1848. 
fucus costatus Mert. Jun. L ote 
Costaria Turneri Post & ‘ed “lust. Alg. 12. pl. 2 
Plant from five inches to a foot broad; stipe expanding 
from the base into a plain undivided reticulate blade. Root- 
lets dichotomously branched. 
Common on the Californian coast. 
Costaria costata Sag, ), nom. = 
Fucus costatus Turn c. pl. 22 
Costaria Tan a at ae Brit, ret p. XXXIX 
Plant seldom over two inches broad; lanceolate, two feet 
ong. Rootlets nearly simple. 
As far as I can discover, this plant has never been reported 
for the Californian coast before. The information I have been 
able to obtain in reference to its distribution is from Agardh 
(Species, Genera et Ordines Algarum, 139-140). He says 
of its habitat, ‘‘On the Pacific shores of Central America or 
?North America.” The interrogation mark before North 
America is explained by a sentence a few lines further on 
*Turner, Nhe ~ etc. 4:—.p/. 226, 
*Alg. Brit., Synopsis p. xxxix. 
Praia XX.—No. 4, 
