Algae. 251 



a) Articuli compressed sagittate, reniform, or truncate, 

 pinnately branched; genicuia unizonal, lineaeform. 

 Conceptacles on the surface of tlie compressed arti- 

 culi. Sect. III. Arthrocardia. 



b) Articuli cylindrical or compressed sagittate, or linear, 

 pinnately or irregularly branched. Conceptacles coni- 

 cal or hemispherical, prominent on the margins of the 

 compressed articuli, or on the surface of cylindrical 

 articuli. Sect. IV. Marginisponim. 



B. Mother cells of the propagating cells generated in the me- 

 dulla; genicuia unizonal or multizonal; articuli cylindrical, 

 compressed, sagittate or truncate; ramification pinnate, dicho- 

 tomous, verticillate or irregulär. Conceptacles vcrruculose, 

 globular or pear-shaped. 

 I. Genicuia multizonal; ramuli starting from tiie genicuia. 



a) Articuli cylindrical, ramuli verticillate. 



Gen. II. Metagoniolithon. 



b) Articuli flat, di-trichotomously branching. 



Gen. III. Litharthron. 



II. Genicuia not specially differentiated; main branches dicho- 

 tomously divided, with compressed articuli; ramuli pin- 

 nate, with cylindrical articuli. Gen. IV. Lithothrix. 



III. Genicuia unizonal, ramuli starting from articuli. 



a) Conceptacles sessile immersed in articuli or pinnulets. 



Gen. V. Cheilosporiim, 



1. Fertile articuli sagittate with pointed wings, concep- 

 tacles immersed in the upper margins of the sagit- 

 tate articuli. Sect. I. Eucheilosporum. 



2. Fertile articuli sagittate or reniform with round or 

 truncate wings, conceptacles immersed in the outer 

 margins of the articuli, or in the surface of the 

 articuli. Sect. II. Alatocladia. 



3. Articuli compressed hexagonal, conceptacles wart- 

 like, on the surface of the articuli or immersed in 

 the pinnulets. Sect. II. Serraticardla. 



b) Conceptacles stalked, mostly takin'g the place of a 

 segment. 



1. Branches pinnated. Gen. V. Coralllna. 

 a. Pinnules simple or less decompound. 



Sect. I. Officinales. 

 ß. Pinnules densely decompound. 



Sect. II. Halypiion: 



2. Branches dlchotomous. Gen. VII. Jania. 



Okamura. 



Yenbo, K., Contribution to the study of the Phytoplank- 

 ton of Japan. With pl. X — XII. (Journ. of the Imp. Fisheries 

 Bureau. Vol. XIV. No. 2. p. 33—69. 1905. Japanese.) 



Illustration of our common plankton-diatoms (50 sp.) collected 

 near Misaki in the Province ot Sagami, in April, 1905. 



Okamura. 



Yendo, K., Principles of svstematizing Corallinae. (Bot. Mag. 

 Tokyo. Vol. XIX. No. 226. Dec. 1905. p. 115—126.) 



After having given a short history of the study of Corallina- 

 ceoiis plants, the author says that the most reliable character is, no 



