636 University of California Puhlications in Botany [Vol. 8 



No genus of the Laminariaceae, not even excepting the genus 

 Lamvnaria, is so confusing as to specific segregation within its limits 

 as Alaria. Ruprecht, J. G. Agardh, Kjellman, Setchell, and Lendo 

 have struggled with it and assisted both in clearing some species and 

 confusing others. The arrangement of our species by Setchell (1912a) 

 and the monograph of the genus by Yendo (1919) are followed in their 

 essentials in our account. We cannot, however, follow Yendo in all 

 his distinctions since our experience leads us to assign somewhat 

 different degrees of importance to certain of the characters which he 

 stresses. We are not able to apply the distinction into "Holosoria" 

 and "Metasoria" with such precision even as Yendo (1919, pp. 24-26) 

 indicates as possible. 



Key to the Species 



1. Midrib solid throughout 2 



1. Midrib fistulose at intervals 9. A. fistulosa (p. 644) 



2. Sporophylls short 3 



2. Sporophylls long 7 



3. Sporophylls narrow 4 



3. Sporophylls broad 5 



4. Blade long and broad above 2. A. praelonga (p. 637) 



4. Blade short and narrow 1. A. nana (p. 636) 



5. Stipe long, very much flattened 3. A. tenuifolia (p. 638) 



5. Stipe short, cylindrical 6 



6. Midrib broad 4. A. marginata (p. 640) 



6. Midrib narrow 5. A. Pylaii (p. 641) 



7. Sporophylls narrow 8 



7. Sporophylls broad 8. A. valida (p. 643) 



8. Cross-section of midrib elliptical 6. A. dolichorhachis (p. 642) 



8. Cross-section of midrib oblong 7. A. lanceolata (p. 642) 



1. Alaria nana Schrader 



Plants anchored by firm strong hapteres; stipe 4.5-7 cm. long, 

 robust, 5-8 mm. diam., terete; rhachis 2-4 cm. long, slightly com- 

 pressed, passing gradually into the midrib ; blade usually widest near 

 the base tapering rather abruptly below and gradually above, with 

 some specimens nearly linear, 40-60 cm, long, 3-8 cm. wide ; midrib 

 prominent, 4—6 mm, wide, nearly rectangular in cross-section ; sporo- 

 phylls 25-50 in number, linear to slightly elliptical, 6-12 cm. long, 

 8-15 mm, wide, rounded at the outer end, tapering rather abruptly at 

 the base to a distinct short stipe, sori covering both entire surfaces. 



Growing on rocks in the upper part of the littoral belt, in localities 

 exposed to the action of the heavy surf, in company with Postelsia 

 palmaeformis and Lessoniopsis littoraHis, Port Renfrew, Vancouver 

 Island, British Columbia, 



