ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 09 



upon a glandular cell degenerates as the latter develops, leaving a 

 membranous coating over the gland ; (4) the function of the gland is 

 possibly to secrete a mucilaginous substance ; (5) the glands found in 

 the lamina of Birome and Undariopsis will probably prove to be similar 

 to those of Undaria in their mode of development and function. 



Cytology of Cutleria and Aglaozonia.* — S. Yamanouchi, in a 

 preliminary note, gives a brief account of his cytological studies of 

 Cutleria multifida and Aglaozonia reptans. Of the former species he 

 describes the gametogenesis, the fertilisation and germination, and of 

 the latter, the zoosporogenesis. Finally, he summarises his results as 

 follows : — 1. The nucleus of both male and female plants of Cutleria 

 multifida contains 24 chromosomes ; and the male and female gametes 

 produced contain the same number. 2. In the union of gametes the 

 number is doubled, and 48 chromosomes appear in the sporelings, 

 which develop into the Aglaozonia form of Cutleria. Therefore it is 

 evident that the individual bearing the name of C. multifida represents 

 the gametophytic phase of the species, 24 being the gametophytic 

 number of chromosomes ; and the Aglaozonia form of Cutleria 

 represents the sporophytic phase of the species, 48 being the sporophytic 

 number. 3. Aglaozonia reptans contains 48 chromosomes, and tbe 

 number is reduced in zoospore formation, the zoospore containing 24 

 chromosomes. Tbe zoospore, with the reduced number of chromo- 

 somes, germinates without conjugation. Although the nuclear details 

 of the sporelings of A. reptans have not yet been followed, it seems 

 evident that A. reptans represents the sporophytic phase of the indi- 

 vidual whose gametophytic and sporophytic numbers of chromosomes 

 are respectively 24 and 48. Probably A. reptans, as it occurs in nature, 

 is identical with the Aglaozonia form of Cutleria multifida which he 

 has grown under culture, and is now determined to be the sporophytic 

 phase of the species. 



Oospheres in Sargassum. f — M. Tahara writes a preliminary note on 

 the periodical liberation of the oospheres in Sargassum, which he has 

 observed at the Misaki Marine Station. The species studied was 

 S. enerve, which is very common in the vicinity, and often forms a 

 considerable mass. Its fruiting season begins at the beginning of 

 December and continues probably till the end of April. Details are 

 given of the observations made, and the results are shown in a short 

 summary. 1. Liberation of oospheres in Sargassum takes place simul- 

 taneously, not only for a given plant, but also for all the plants of the 

 locality. 2. This simultaneous liberation proceeds in fortnightly crops 

 on a particular day with a fixed interval after the highest spring tide ; 

 interval varies, however, in different species. 3. The oospheres in one 

 and the same receptacle are not discharged at one time, but in two or 

 three successive fortnightly crops. 



West Indian Floridese.J — F. Borgesen describes some new species 

 of Floridere collected in the sea around the Danish West Indies, and 



* Bot. Gaz., xlviii. (1909) pp. 380-6. 



t Bot. Mag. Tokyo, xxiii. (1909) pp. 151-3. 



% Bot. Tidsskrift, xxx. (1903) 19 pp. (tabs, and figs, in tsxt). 



