210 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



flattened above, to 2-3 mm wide, below subcylindrical, to 2 mm diam. ; 

 tetrasporangia abundant in the branchlets of sporangial plants ; axis struc- 

 turally showing a medulla of coarse and small longitudinal filaments 

 intermixed, the inner cortex of moderately large cells, the outer of radial 

 rows of small cells. 



Kylin 1941, p. 13; Smith 1944, p. 244, pi. 56, fig. 1. 



Mexico: Baja California, common on rocks at South Bay, I. Cerros, 

 no. 34-633 (tetrasporangia!), 10 Mar. 1934. 



V. delicatula n. v.^24 

 Plate 66, Fig. 1 



Plants tufted, to 13 cm tall, blackish purple, tough; slender, uni- 

 formly about 1 mm diam. throughout, erect axes subsimple to, in fully 

 developed specimens, densely bilaterally pinnately beset with simple 

 branchlets about 1 mm apart, commonly rather uniformly about 15 mm 

 long, reaching 2-3 cm, these tapering somewhat to their bases. 



These are smaller, slenderer, and much more distichous in appearance 

 when fully developed than the typical plants collected at the same station. 

 They show some similarity to Prionitis Lyallii f. densissima Harvey 

 (Phyc. Bor.-Amer. no. 948), but are proportionately more slender. 



Mexico: Baja California, on rocks at South Bay, I. Cerros, no. 34- 

 637 (TYPE), 10 Mar. 1934. 



Prionitis kinoensis Dawson, /. 



Plants to 2 cm tall, bushy, branching dichotomous, complanate, the 

 branches compressed above, 1.0-1.5 mm diam., later with short divergent 

 secondary branches along the margins of the lower segments ; structurally 

 showing a very dense medulla internally of intertwined filaments, out- 

 wardly of looser and larger (anastomosing?) filaments, supporting a close 

 cortex of anticlinal cell rows. 



Dawson 1944, p. 284, pi. 67, fig. 1. 



These plants suggest P. kinoensis in miniature, and probably repre- 

 sent only a dwarf form of that species. 



Ecuador: Archipielago de Colon, on rocks, I. Bartolome, no. 34- 

 344, 23 Jan. 1934. 



124 Prionitis filiformis v. delicatula n. v.— Plantae caespitosae, ad 13 cm alti- 

 tudine, circa 1 mm diam. ubique, axibus erectis subsimplicibus aut ramulos 

 simplices, 1.5, raro ad 3 cm long., intervallis 1 mm, aeque, bilateraliter, pinnate 

 praebentibus. Planta typica in loco dicto I. Cerros, Mexico, legit W. R. Taylor 

 no. 34-637, 10 Mar. 1934. 



