676 University of California Publications in Botany [Vol.8 



Growing on rocks, logs, etc., in sheltered localities in the upper 

 third of the littoral belt. Point Defiance, Tacoma, Washington. 



Gardner, Genus Fucns, p. 35, pi. 32. 



It is not easy to delineate the distinctive characters of this form 

 associating it with the memhranaceus group, rather than with the 

 evanescens group. In many specimens the midrib is quite indistinct. 

 The cryptostomata characters are quite as much of the one group 

 as of the other. It is provisionally placed with the former group 

 largely on account of the predominance of inflated receptacles, on the 

 membranaceous character of the fronds and on the color. 



Two forms of Fucus were found growing at Point Defiance, repre- 

 senting an interesting case in distribution. Forma limitatus occupied 

 for the most part the extreme upper portion of the littoral belt, and 

 grew on logs and boulders. F. furcatus f. reflextis grew on boulders 

 and occupied the lower third, with an occasional plant of either form 

 invading the central part. 



4. Fucus membranaceus f. abbreviatus Gardner 



Fronds short, membranaceous, flabelliform, profusely branched, 

 8-14 cm. high, dichotomous or in part secund, yellowish brown; seg- 

 ments strict, narrowly cuneate to sublinear, 5-9 mm. wide, apices 

 truncate midrib moderately prominent, only slightly evanescent, alae 

 thin, cryptostomata few in the lower portions of the plant, 20-40 

 per sq. cm. in the terminal segments, small but conspicuous on drying ; 

 receptacles bifid, mostly swollen wdth mucilage, apices acuminate or 

 in part blunt, somewhat divergent, sharply delimited ; conceptacles 

 numerous and prominent. 



Growing on rock ledges exposed to heavy surf, in the upper limit 

 of the littoral belt. Sitka, Alaska. 



Gardner, Genus Fucus, 1922, p. 32, pi. 27. 



Forma abbreviatus grew on the same islet on which the forma 

 acuminaius was found growing, but mostly higher up, some specimens 

 were even above mean high-tide level. It differs from forma acu- 

 minaius principally in having shorter fronds, relatively much broader 

 and shorter receptacles, fewer cryptostomata, and it is less mucilagin- 

 ous. It seems closely akin to J. Agardh's Fucus bursigerus from 

 Spitzbergen, but it is more robust, and much more profusely branched 

 than his description and figure call for (cf. J. Agardh, Spets. Alg. 

 Till., 1868, pp. 41, 42, pi. 3). We have seen the specimen of Kjellman's 



