174 THE BOTANICAL MAGAZINE. LVo:. xxxiii. Ko. 3«3. 



question while I was observing the behaviour of the spores, but 

 I could not ascertain their actual copulation. In their resting 

 stage as well as in the beginning of their germination, I saw 

 alwa\'S a single eye-spot and a single chromoplast in each. It 

 requires a more extended study ou the behaviour of the swarm- 

 spores of thQ Encoeliaceae before yvc can accept the term 

 gametangia for the plurilocular sporangia. 



As above stated, I tried the culture in two beakers. Ihey 

 were of equal shape and size, measuring 15 cm in height and 

 10 cm in diameter. On 7th. April, 1918, swarmspores still 

 actively swimming about, liberated from the fronds which had 

 been brought to the laboratory' from the sea-shore five days 

 before, were put in the A beaker ; and those from the fronds 

 brought in on the previous day, in the B beaker. Both w^ere 

 covered wath fine cheese-cloth to prevent the dust from getting 

 into the water. The .\ beaker was placed in a glass vase of 

 much larger dianaeter and height filled with fresh sea-\vater. The 

 B beaker was provided wath nothing outside. Both w^ere 

 placed on the same table in a corridor well-lighted but not 

 under direct sunlight. Natural sea-water twice filtered through 

 an ordinary filter-paper was at first used to fill the beakers. 

 Within a few da^'s after the start of the culture, I found 

 Infusoria in the water, though not abundant. The water was 

 changed every three days with natural sca-w'ater newly drawn 

 each time and filtered through the cotton in the waj' described 

 in the preceding paper,^^ p. 88, foot-note. The water could 

 remain free from the animal throughout the whole time of the 

 culture. 



The temperature of the water in the B beaker ranged 

 from 6°C. to 14°C, during the culture period. The 

 maximum daily fluctuation was read less than 3°C. This 

 temperature was nearly similar to that of the surface water 

 about Otaru Bay in the respective seas*on, as has been detailed 

 in the preceding paper. The temperature of the water in the 

 A beaker was always about 2° lower than in the B beaker. I 



]) Bot. ^[ag;izine, Tokyo. Vol. XXXIII, No. ;;88. 



