36 Universilij of California Puhlications in Botany [Vol. 10 



Growing on boulders in the extreme lower littoral belt. Kadiak 

 Island and Ritka, Ala.ska. 



Til June, 1910. I first observed this form growing in the harbor at 

 Sitka, but at that time I was unable to obtain good fruiting specimens. 

 On my second visit to the same place in July, 1917. 1 located a large bed 

 containing thousands of plants growing along the extreme low-tide 

 level, and I was able to procure a number of good fruiting specimens, 

 although the summer season does not seem to be its best fruiting season. 

 This form may be readily distinguished from all others by its width, 

 being the widest form in the vicinity, its membranaceous alae, its very 

 dark lower portion, and usually yellowish upper portion, and by its 

 much crisped habit of growth. Some of the plants of this species 

 collected by G. B. Rigg at Kadiak Island are the widest specimens of 

 Fucus that have been reported, some of the fronds measuring over 

 seven centimeters in width. 



Fucus evanescens Ag. 



Plate 1, figure 2 



"Fronde supra medium costata linear! integerrima subdichotoma 

 evesiculosa, receptaculis compressis." 



"Ad Saehalien, Tilesius; ad Kamtschatka, Chamisso; unde speci- 

 mina communicaverunt. ' ' 



' ' Simillimus F. vesiculosa, sed diversus. Frons magis flabelliformis. 

 Segmenta cuneiformia. brevia, poris tenuissimis sparsis pertnsa. Costa 

 subobsoleta & supra frondem parum elevata. ante apicem omnino 

 evanida, ita ut frons superne sit enervis. Receptacnia brevia, saepe 

 bifida, compressa nee inflata; tuberculata. tuberculis sparsis fere ut in 

 Fuco serrato. glomerulis in gelatina filamentosa immersis. " 



Agardh, Sp. Alg.. vol. 1, part 1, 1820. pp. 92, 9:3. 



Fronds moderately robust sometimes arborescent, usually decidedly 

 coriaceous, dichotomous or in part subsecund, olive brown, to yellowish 

 above; segments often quite foliaeeous and crisped, in some, narrow, 

 cuneate to linear, midrib more or less distinct, in some cases vanishing 

 more or less in the terminal segments, cryptostom.ata few to many, 

 scattered; receptacles very variable in shape and size, long and narrow 

 to short and blunt, bi- tri-furcate. 



Growing in the littoral and upper sublittoral belts. From Bering 

 Sea to Coos Bay, Oregon. 



In Icones Algarum Ineditae, 1821, XIII, Agardh repeats the first 

 paragraph of the above quotation in explanation of table XIII, which 

 illustrates this species, and adds. "Specimen delineatum. ad Kamts- 

 chatka lectum, dedit clarissiiiius (Itami.'^so. Fig. 1. Planta magni- 

 tudine naturali." T have here reproduced this figure on plate 1. 



