172 THL' BOTANICAL MAG A ZTNK [Vo'. xxxin. No. 393. 



examinations on these alsrac lead us to think that the 

 origin of the caespitose fronds may not be the same with 

 them all. In some species which are diagnosed " frons 

 Ccespitosa," the " fronds " are the result of the laciniation of 

 a simple blade as it develops. In others, they are separate 

 shoots starting from a simple, disc-shaped root, or a prostrate 

 primordial thallus. Still in others, they appear to be a mere 

 aggregation of several shoots perhaps germinated from several 

 spores aggregated together. Not seldom, they ma\' be branches 

 starting from a stunted stem that can be discerned only in an 

 early stage of development of the plant. Homoeostroma lati- 

 folium J. Ag.,^' which resembles Phyllitis Fascia very much in 

 habit of growth, belongs to the second category. Reinke's"^ 

 observation, however, points to the Phyllitis fronds as belonging 

 to the third. 



In the vicinity of Otaru Ba}', young shoots of Phyllitis 

 begin to appear late in October at the upper limit of the 

 sublittoral region. They become soriferous in the latter part of 

 December and continue in the same state tnitil the end of 

 April of the next year when the sori are fully matured. At the 

 end of June, they^ are mostly washed aw^ay from the substratum 

 and in July we can find them no more growing. 



For several years I have observed the sori discharge the 

 spores late in December and in March-April. Whether the 

 spores are matured continuousU' during this time or they are 

 periodically so, I am not able to say conclusively at present. The 

 presence of more than one soral patch on ii frond, however, 

 points to the second view. It is a fact that the spores are 

 much more richly discharged in spring than in winter. 



On 6th. April, 1918, I took some fronds with matured sori 

 and put them in a large glass vase filled with fresh, clean 

 sea-water. The vase was placed on a desk in the laboratory at 

 Sapporo. Within 24 hours after setting thus, I (bund, as usual, 

 the spores aggregated themselves in the well-lighted side of the 



1) Yemjo: Monograph of the Genus Alaria, p. 30. (Journal of the College of 

 Science. Tokyo. Vol. XLIII, Art. 1, T.I19). 



2) RErNKE: 1. c. 



