1906] SIMONS—SARGASSUM FILIPENDULA 165 
system. Most of the cells in the storage system are large. HANSTEEN 
found them empty in alcoholic material of Sargassum, but he did not 
doubt their function to be that of storage, because he had found much 
reserve material in similar cells of living Fucus. The conducting 
system consists of an axial cylinder of long cells with small diameter 
and oblique end walls. These cells are believed by HANSTEEN and 
others to function as sieve tubes. The cells of the three aes 
communicate by pores. 
HANSTEEN observed in the storage cells of Fucus serratus a 
several other types, spherical grains of different sizes, which he named 
fucosan. He believes that the same structures have been variously 
considered as fat, proteid, and starch by other observers. The grains 
do not stain blue with iodin, and are soluble in water. HANSTEEN, 
who made a chemical analysis to determine their composition, con- 
siders them as a carbohydrate with the formula (C;H,,O,),.  CRaTo 
(°92) described in Chaeto pteris plumosa spherical or elliptical bladder- 
like structures which he named physodes. He reported (’93) that 
they contain phloroglucin as a constant ingredient, function in direct- 
ing the chemical exchange and transportation of food material within 
the cell, have motion, and are independent cell organs like the nucleus 
and chromatophore. Crato stated further that HANSTEEN had 
confused various cell contents, and that fucosan grains and physodes" 
are the same. KocH (’96) denied the presence of phloroglucin in 
these bodies. Ina later paper HANSTEEN (:00) again discusses fuco- 
san grains. He maintains that CRATO’s physodes are fucosan grains, 
and that they are not independent cell organs but products of the 
phaeoplast. HANSTEEN has made no further chemical analyses to 
determine the nature of the bodies, but holds that they surely repre- 
sent a product of photosynthesis. HANSEN (’95) after an investiga- 
tion of several forms (Dictyota dichotoma, Taonia alomaria, Haly- 
seris polypodioides, Asperococcus, Hydroclathrus, and Cystoseira), 
states that the Phaeophyceae contain oil and no starch, and OLTMANNS 
(:04) expresses the same view. It is seen therefore, that the character 
of the reserve material in the cells of the Phaeophyceae is still some- 
what problematical. 
Every stem and leaf structure in Sargassum filipendula, as in other 
species studied, develops through the activities of a three-sided apical 
