THE FUCACE/E OF JAPAN. Öi) 



= Fucus pihilifcr Turx.: Hist. Fuc. Vol. T. Tab. Ho. 



= Fucus mieroccratius Trux.: Illst. Fuc. Vol. 11. ]>. l.j.j. Tab. loO, 



= Sargassum microceratium Ao.: Dec. No. 3'5. — J. Ac: Anal. Al;,^ 



Cent. III. p. 59. 

 =Myagropsis microeeratia KI'tz.: Tab. I'liyc. X. Taf. 94. 



Description of the species. Frond attains 2-4.5 foet in height 

 with a knotty, rugose, disc-shape root at the base. Generally 

 several shoots start from the surface of the same root, giving the 

 appearance of a multicipital frond. A primary shoot is nothing 

 but a simple lanceolate or linear leaf attached to the surface of 

 a circular disc by a ver}' short petiole. It gradually elongates 

 and divides decompoundly pinnately, with the margin entire; an 

 immersed midrib traverses the whole length of the lamina and 

 a series of cryj^tostomata is found on each side of the latter. 

 The jjinme are l.ü-2.0mm. wide and the entire length of a leaf 

 measures -3-6 cm. 



The axial part of a primary shoot develops to form the 

 main stem of a frond, thickening simultaneously into a compressed 

 or ancipitous rachis. The lower portion of the stem has several 

 leaves arising alternately from the ancipitous edges. These leaves 

 are essentially similar to the primary shoots in every respect. 

 In an old stem, these lower leaves are generally worn off, leaving 

 conical scars at the points of insertion. The stem in the upj^er 

 portions is subterete, with rounded margin, measuring 1.5-2.0 mm. 

 in breadth. The fidcrant leaves in the upper portions are fili- 

 form, subterete, pinnately divided or apparently dichotomous, or 

 sometimes simple, with the apices of the segments sharply pointed. 

 No distinct midrib is found in the upper leaves which have 

 cryptostomata on the margins. 



Vesicles are spherical, without cryptostomata, ending abruptly 

 in a slender stipe as long or even twice as long as the diameter 



