258 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 17 



Type: Holotype is Dawson 1897, May 18, 1946, on sheet 5631, 

 including vial 4176, in HAHF. 



Type locali'ty: Cast ashore, Ensenada de San Francisco, Sonora, 

 Mexico. 



Additional material: D. 7009a, on old breakwater, south side 

 of Bahia San Gabriel, Isla Espiritu Santo, Baja Calif., Mexico, Mar. 



The three available specimens of this plant, all of them cystrocarpic, 

 are so distinctive in size, branching and habit as to be distinguished 

 readily from the other species treated here. They show some resemblance 

 to Grateloupia dichotoma J. Ag. from the Mediterranean, but lack the 

 pinnate proliferations and blunt ultimate segments of the primary dicho- 

 tomous frond of that species. 



Grateloupia? squarrulosa Setchell & Gardner 



Setchell and Gardner 1924, p. 780, pi. 81-82; Dawson 1944, p. 281. 



Inasmuch as no new material of this plant has been collected little 

 can be added to our knowledge of it. As Setchell and Gardner pointed 

 out, there seems to be marked relationship between this plant and G. 

 johnstonii, although apparent differences are observed in form and posi- 

 tion of the ultimate branches. Structurally they also show a relationship, 

 but one which is not readily assayed. The presence of the peculiar fila- 

 ments of large diameter (up to 20-25 jx) in the medulla is particularly 

 striking. Furthermore, the type localities of G. squarrulosa and G. john- 

 stonii are very near each other. Further field study and the liquid pre- 

 servation of fertile material are needed for the solution of this problem. 

 The original description is quoted here for the convenience of future 

 students of Mexican algae. 



"Fronds 40-55 cm. high; branching exceedingly variable, of 5-8 

 orders; main frond more or less percurrent, flat, 5-15 mm. wide, pin- 

 nately branched at the margins, with branches very variable in size, some 

 erect, some patent, others recurved, all with broad bases; the surface, 

 as well as the margins of the main frond, more or less covered with 

 branches, the whole frond thickly beset with short, blunt, branched 

 spines ; reproduction unknown ; color dark purplish red." 



Type: Holotype is Johnston 60, June 1921, on sheet 1368 in the 

 Herbarium of the California Academy of Sciences, San Francisco, 

 California. 



Type locality: Cast ashore, Isla Smith, Gulf of California, 

 Mexico. 



