252 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 17 



Thalli to 25 cm. long, complanate except at the very base, consisting 

 of several to many flat, linear-lanceolate blades from a relatively small 

 discoid holdfast; blades simple or commonly once forked near the base, 

 sometimes once divided above or proliferous when injured, narrow-cun- 

 eate below to a short, compressed or flattened stipitate base, attenuate 

 above, 7-13 mm. broad, or sometimes to 25 mm., 150-250 ju, thick, the 

 margins normally entire ; medulla rather dense, mostly of longitudinally 

 arranged filaments about 5 /a in diameter except along the margins next 

 to the cortex; cortical filaments of 5-6 (7) cells; tetrasporangia cruciate, 

 25-30 fi long, 11-15 IX wide, scattered through the cortex just 6elow the 

 surface, causing little or no nemathecial modification; sexual plants not 

 seen. 



Type: Holotype is D. 9270, May 2, 1950, on sheet 59322, includ- 

 ing vial 4172, in HAHF. 



Type locality: Rocks near low tide line, Punta Entrada, Isla 

 Magdalena, Baja California, Mexico. 



Additional material: Pacific Baja Calif. — D. 9502, Punta 

 Abreojos, Apr. ; D. 9077, south shore, Isla Este, Islas San Benito, Apr. 



This species shows several superficial characters in common with G. 

 schizophylla, but unlike that plant has numerous blades arising from 

 a common base, and has a moderately dense medulla. It is also con- 

 siderably smaller overall than examples of G. schizophylla from Baja 

 California. 



Grateloupia filicina (Wulfen) C. Agardh 



C. Agardh 1822, p. 223; Dawson 1950, p. 155, fig. 29 (as var. 

 lomentaria Howe). Fucus filicinus Wulfen, in Jacquin 1786-1796, p. 

 157, pi. 15, f. 2. Lomentaria drouetii Dawson 1944, p. 309, pi. 46, figs. 

 1-2, pi. 74, fig. 2. 



Thalli 8-12, or to 20 cm. high, lubricous, consisting of one to several 

 abundantly multifariously branched, percurrent or indefinite cylindrical 

 to compressed axes from a simple discoid holdfast ; primary axes common- 

 ly 1.5-2 mm. in diameter, sometimes to 3 mm., giving rise to 2 or more 

 orders of more slender, long-attenuated branchlets, the ultimate ones less 

 than 200 fx in diameter ; transection of upper thallus parts showing a very 

 extensive medulla of sparse, slender, ramified filaments 7-8 jx in diameter 

 surrounded by a relatively thin rim of solid cortical tissue, or the inner 

 medullary area often in part or entirely hollow; cortex consisting of 

 about 2 partially incomplete inner layers of ± rotund cells giving rise to 

 anticlinal filaments of 2-3 smaller cells; tetrasporangia scattered in the 



