292 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



erally 1-2 cm long, which are likewise percurrent, but in pyramidal 

 fashion bear alternate cylindrical to somewhat club-shaped branchlets 

 0.3-0.5 mm diam. which fork alternately 1-3 times. 



The sparingly divided main axes of these plants are somewhat virgate, 

 and the close lateral branches form small paniculate clusters. They do 

 not resemble Phyc. Bor.-Amer. no. 1093, called L. pacifica by Kylin 

 ( 1941, p. 42), which as a whole has a pyramidal habit and the branchlets 

 of which are short and much more congested than those of these speci- 

 mens, and the plants more firm in texture. 



Mexico: Baja California, on rocks at Pt. Hughes on Cabo San 

 Lazaro, no. 34-607 (TYPE), 7 Mar. 1934. 



Laurencia congesta n. sp.^^^ 



Plate 99, Fig. 1 



Plants to 2 dm tall, bushy, dull blackish red ; axes somewhat denuded 

 below, 1.5-2.0 mm diam., erect, occasionally with one or two equal main 

 divisions but generally simple, irregularly beset with subsidiary lateral 

 branches; lateral branches erect, irregularly, chiefly alternately divided, 

 the lower branchlets subsimple or 1-4 times pseudodichotomously forked, 

 the subsidiary axes and their main divisions deliquescent above, producing 

 in the upper parts of the plant densely congested corymbiform clusters; 

 ultimate branchlets erect, somewhat clavate, about 0.5 mm diam. 



The habit of this plant is extremely characteristic, for the other larger 

 bushy species when of compact habit are essentially paniculate, rather 

 than corymbose with the axes disappearing into more or less even-topped 

 clusters. 



Ecuador: Archipielago de Colon, on rocks in the littoral near Black 

 Beach Anchorage, I. Santa Maria, no. 34-217 B (TYPE), 17 Jan. 1934. 



Laurencia oppositoclada n. sp.^^^ 



Plate 99, Fig. 2 

 Plants to 25 cm tall, dull blackish red, subcartilaginous below, only 

 the young parts adhering to paper; erect bushy, the leading percurrent 



185 Laurencia congesta n. sp. — Plantae ad 2 dm altitudine, fruticosae, axibus 

 infra paululum denudatis, erectis, plerumque simplicibus, ramos laterales, sub- 

 sidiarios, erectos irregulariter praebentibus; ramis magna ex parte alterne divisis, 

 ramulis inferioribus subsimplicibus aut 1-4-subdichotome furcatis, axibus primariis 

 supra deliquescentibus; in fascicules coryrabiformes et confertos terminantibus; 

 ramulis ultimis erectis, subclavatis, circa 0.5 mm diam. Planta typica in loco dicto 

 I. Santa Maria, Ecuador, legit W. R. Taylor no. 24-217B, 17 Jan. 1934. 



1S6 Laurencia oppositoclada n. sp. — Plantae ad 25 cm altitudine, subcartila- 

 gineae, erectae fruticosaeque, axibus primariis percurrentibus ad basim sparse 

 divisis, ramis ramulisque determinatis, intervallis 3-5 cm, magna ex parte sub- 

 oppositis, singulis aut ad 3-4 simul, prope cacumina subpaniculatis factis, 0.5-1.2 

 mm diam., 3-15 mm long., clavatis ad subcylindricos, basim paululum contractam, 

 apicem obtusum ad truncatum habentibus. Planta typica in loco dicto I. Santa 

 Maria, Ecuador, legit W. R. Taylor no. 34-217 A, 17 Jan. 1934. 



