US BOTANCTAL MAGAZINE. [Voi.xix, 



group. He held that the "apothese" originated from the medulla, and 

 the " tetragonia "' from the cortex ; and pointed out similar examples out 

 of other Floridte to support his opinion. By such citations he discredited 

 Lamouroux's opinion as well as his former remarks. 



Harvey, Areschoug and others seem to have paid but little attention, 

 if at all, to the work of Trevisan. Areschoug in J. Agardh's " Species 

 Genera et Ordines Algarum " has given us a classical work, in which he 

 mentions under the Coralline five genera, viz., Ampliiroa Lamx., Artliro- 

 cardia Aresch., Cheilosporum Aresch., Jania Lamx. and Corallina Lamx. 

 His system is based chiefly on the position of conceptacles (Keramidia) and 

 on the form of articuli. 



In 1819 J. E. Gray^ proposed a new genus Lithothrix, basing it on 

 a plant from Vancouver Island, B.C. The definition of the genus was 

 rather ambiguously drawn up, and whatever comment was not given on 

 the point to distinguish it from other genera. Its stand was first put 

 in doubt by Farlow 2) ; and finally the species was referred by Anderson 3 ' 

 to Ampliiroa. 



In 1881 Graf zu Solms-Laubach 4) published his excellent work 

 " Corallina." In this the author held Jania corniculata L. as nothing 

 but a form of Jania rubens L. He noticed the pinnation of the ramuli 

 in the former plant to be similar to that of Corallina Lamx. Upon this 

 ground Jania and Corallina were again united. Hauck, 5) Schmitz 6) and 

 several other recent algologists have followed his opinion ; and furthermore 

 they have reduced Arthrocardia Aresch. to a synonyme of Cheilosporum 

 Zanard. T; 



In the list of Corallinaceous algse of Japan 1 8) have referred the plants 

 to the various genera as best as I could and have provisionally introduced 

 some new subgenera, such as S&rraticardia, Marginisporum, etc., but without 

 definitions. These subgenera will be enunciated in detail in due places. 9) 



In my paper on genicula of Corallinaa, p. 41, I have noted that Am- 

 pliiroa stelligera can scarcely be retained in that genus, and that Ampliiroa 



1) Journal of Botany. Vol. V. p. 33. 



2) Proce. of Amer. Acad, of Art and Sc. Vol. XII. p. 329. 



3) Zoe. Vol. II. p. 225. 



4) Corallina. (Fauna und Flora, v. Golfes v. Neapel. 4. p. 6.) 



5) Meeresalgen. p. 297. 



6) System. Uebersicht. (Tlora. 1889. p. 455.) 



7) Schmitz mentioned Areschoug as the proposer of Cheilosporum. 



8) Enumeration of Cor. Alg. (Bot. Mag., Tokyo. Vol. XVI.) 



9) Cf. Journ. of Science, Tokyo. Vol. XX. Art. 12., which will appear soon. 



