NO. 2 DAWSON: MARINE RED ALGAE OF PACIFIC MEXICO 251 



Recent authors dealing with the northeast Pacific algal flora have 

 followed Kylin (1941) in recognizing this variable and widespread 

 species as distinct from the South American Grateloupia cutleriae assem- 

 blage. Kylin, however, failed to validate his name {G. calif orntca) by 

 giving a Latin diagnosis. A comparison of a number of Mexican and 

 United States specimens with plants from Callao, Peru, identified by 

 Taylor as G. schizophylla Kiitz., has led me to the feeling that the North 

 and South American plants are probably conspecific, and that all of them 

 may best be dealt with at the present time under Kiitzing's valid name. 

 The specimens of G. schizophylla examined from Peru are undoubtedly 

 the same as those illustrated by Howe (1914, pi. 61-62) and seem rea- 

 sonably identifiable with Kiitzing's plant from Chile (Tab. Phyc. 17, 

 pi. 36). The distinctions between these and G. cutleriae Kiitz., which is 

 said by Kylin to be larger, broader and more coriaceous than California 

 plants, are still not clear. A closer study of variability in the Chilean 

 material is necessary. Among Californian and Mexican plants placed 

 here one finds tetrasporangial examples in which the structure exactly 

 matches that illustrated by Kiitzing (1843, pi. 77, fig. Ill) for G. cut- 

 leriae. Furthermore, collections are present in which plants range in 

 blade-width from 1.7 cm. to 5 or even 6 cm. As Howe (1914) has 

 pointed out, Halymenia ? doryophora Montagne, from Callao, Peru, 

 also remains to be identified in the field, and may prove to be the oldest 

 name for this polymorphic species. 



Although the species presents many variations in size, thickness, 

 branching and proliferation, it appears that excessive branching and 

 proliferation are due largely to an ability to regenerate from almost any 

 part following injury. Plants which have not been attacked by animals 

 or damaged by surf appear in the majority of cases to have solitary, 

 simple or once-forked blades. Lateral and superficial proliferations may 

 develop with age on plants which are at first simple and entire. 



The range of this species along the North American coast appears to 

 extend from the region of Puget Sound to Isla Magdalena, Baja Cali- 

 fornia. In the southern part of the range in Baja California the plants 

 are rare and confined to favorable cool-water regions of upwelling. 



Grateloupia multiphylla sp. nov. 

 PI. 9, fig. 51 



Thallis ad 25 cm. longis, complanatis ; laminis compluribus vel mul- 

 tis e basi communi, lineolanceolatis, simplicibus vel semel furcatis prope 

 basim, attenuatis, 7-13 mm. latis, 150-250 /a crassis; marginibus integris; 

 medulla paulo densa, e filamentis plerumque longitudinaliter dispositis. 



