164 CALIFORNIA. [Alga. 



A very remarkable variety, with a stipitate frond, cartilaginous below, branched ; branches or segments 

 oblong, wedge-shaped, inclining to palmate, strongly nerved at the base : the nerve ramifying over the whole 

 membrane, and visible to the extremity of the frond. In some specimens, these segments are stipitate, and 

 almost resemble the leaves of a Delesseria. Sori in marginal leaflets. — S. serrulatum. Harv. — Frond linear, 

 attenuated, much branched, with a broad nerve at the base, which vanishes about the middle, the margins 

 sharply serrate. 



1. Rhodomenia laciniata. Grev. — Fucus laciniatus. Turn. t. 69. 



2. Rhodomenia polycarpa. Grev. — Crypt, t. 352. 



Another specimen in the Herbarium probably belongs to this species also. 



3. Rhodomenia ciliata; 13. microphylla. 



A remarkable variety, with a lanceolate outline, throwing out stipitate lanceolate leaflets from its margine 

 and disk; these in turn are ciliato-dentate, with lanceolate compressed cilia?, or incipient tertiary leaflets on 

 both surfaces. . 



1. Gelidium cartilagineum. GaiU. — Fucus cartilagineus. Turn. t. 124. 



2. Gelidium corniculatum. Grev. — Fucus corniculatus. Turn. t. 182. 



3. Gelidium? lanceolatum. Harv. MSS. Fronde plana cartilaginea bipinnata, pinnis 

 elongatis basi attenuatis, pinnulis lanceolatis simplicibus suboppositis. 



6-8 inches high, pinnately branched, the branches (pinna?) long, simple, much attenuated at the base and 

 apex ; 1-2 lines broad in the middle, pinnated with tbliaceous, lanceolate, mostly opposite ramuli, from 2-6 

 lines long. Both branches and ramuli are perfectly simple, and preserve their strictly lanceolate figure 

 throughout. 



1. Plocamium coccineum. Lyngb. — Fucus coccineus. Turn. t. 59. 



1. Laurencia obtusa. Lamour. — Fucus obtusus. Turn. £.21. 



2. Laurencia pinnatifida. Lamour. — Fucus pinnatifidus. Turn. t. 20. 



1. Chondrus mamtnillosus. Grev Fucus mammillosus. Turn. t. 218. 



2. Chondrus constrictus. Grev. — Fucus constrictus. Turn. t. 152. 



3. Chondrus vermicularis. Grev. (?) — Fucus vermicularis. Turn. t. 221. (?) 



The specimen which I refer to this species wants the fruit, which in the Chondri is of some moment in 

 specific characters, but the ramification and substance agree with Turner's figure. 



1. Ptilota hypnoides. Harv. MSS.; jugamento compresso filiformi bipinnato, pinnis 

 pinnulisque alternis, his alternatim pinnatifidis (segmentis lanceolatis) et ramulis foliifor- 

 mibus lanceolatis acutis alternantibus. 



This, not excepting our own P. plumosa, is the most beautiful of the genus, and one of the most elegant 

 of marine plants. It is readily known by the small leaflike ramuli, (1 line long) of a lanceolate figure, which 

 regularly alternate with the pinnules, a pinnule and a leaflet being always opposite each other, but standing 

 alternately on the stem. Stems bipinnate, 4^5 inches high, slender, two-edged, all the divisions alternate ; 

 pinnules closely pinnated with lanceolate leaf- like ramuli, between each of which rises a rudimentary branchlet, 

 which in its turn bears also a set of similar little leaves, in an alternate series, opposite each of which is a 

 clavate dark red receptacle full of small grains. 



