1922] Gardner: The Genus Fucus on the Pacific Coast 29 



Forma hesperius seems closely related to or is at least very similar 

 to a narrow, smooth, dark colored form that grows on the Atlantic 

 coast of the United States, which has been referred to different species 

 by different authors. There is a good specimen of it contributed by 

 Howe, under no. 150, to the Herbarium of the University of California, 

 no. 77184. labelled F. eclcntatus. The specimen in Professor Setchell's 

 copy of Farlow, Anderson, and Eaton's Algae Exsiccatae Americae 

 Borealis. no. 108. is almost identical with Howe's specimen, but is 

 referred to F. furcatus. I have examined no. 119 of Hauck and 

 Richter's Phykotheka Universalis, labeled Fucus eclentatus De la Pyl. 

 and contributed by Collins, from Marblehead. Massachusetts. This 

 specimen seems to be identical with the two above mentioned. It is 

 my opinion that all three collections should be referred to F. eclentatus 

 De la Pyl.. and. judging from the figure and description of the type 

 as quoted above, very clearly represent the typical form of the species. 

 None of the Atlantic specimens referred to above have caecostomata. 



Fucus edentatus f. divergens f. nov. 

 Plate 22 



Frondes coriaceae. leves nitidaeque, 28-38 cm. altae, regulariter 

 diehotomae. obscure olivaceo-virides, siccatae atrae; segmentis diverg- 

 entibus 7-11 mm., usque ad 15 mm. latis. inferne cuneatis, superne 

 linearibus, supra axillas paiillo diminuatis, terminalibus truncatis, 

 puncto crescente inconspicuo, costa manifeste distincta, percursa, 

 eryptostomatibus et caecostomatibus nullis vel sparsissimis ; receptaculis 

 3-6 cm. usque ad 12 cm. longis, manifeste definitis, quam segmentis 

 multo latioribus, integris vel 1-2-furcatis, vulgo late divergentibus, 

 apicibus aeuminatis vel acutis; conceptaculis numerosis prominen- 

 tibusque. 



Growing on rock ledges in the lower littoral belt. Kanaka Bay, 

 San Juan Island. Washington. 



Type, Gardner, no. 2338 (Herb. Univ. Calif., no. 201173), July, 

 1910. 



This form of edentatus is closely related to forma hesperius. The 

 fronds average somewhat wider, more robust, the angles between the 

 segments are very much wider and more rounded, and the receptacles 

 mostly deeply bifurcate or single, widely diverging. The average 

 width of the segments is about 10 mm., but a few specimens were found 

 with extremely narrow segments, about 3 mm. These were profusely 

 branched, with wide angles, and small diverging receptacles. Also a 

 few specimens were found with the characters of the form, but were 

 15 mm. wide. These few specimens I have considered as the extremes 

 in individual variation in this particular character. 



