86 



for those slender tonus, which have a central strand with cells of almost equal size in the joints 

 and in the nodes. 



Synoptical Key 



to the Genera of the Corallineac verae. 



1. Fronds branched, articulated, calcified joints separated by horny pliable nodes. Joints consisting 

 of a central strand of filaments and of a more or less developed cortical layer. Conceptacula 

 either occurring as wartlike or conical processes on the joint or immersed in the tissue of 

 the joint. 



(7. Joints cylindrical or broadened; in the central strand rows of short cells are intercalated 

 between rows of long cells all standing vertically one above another. Nodes consist of 

 two or more, — rarely of one, — rows of cells that alternate in the same way as, and 

 have the same size or almost the same size as, the cells in the joint. Conceptacula 

 on the joints Amphiroa Lamx. 



b. Joints cylindrical ; in the central strand the cells have throughout the whole joint almost 

 the same dimension and stand vertically one above another. Nodes consist of many 

 rows of cells which are much smaller and have thicker walls than the cells in the joint. 

 Conceptacula on the joints Metagoniolithon n. g. 



c. Joints flat short elliptical in outline, with a thin central strand of non-calcified, intricated 

 filaments, with cells not standing vertically one above another, and with a considerable 

 layer of calcified cortical cells. Cells of cortical layer large, near central strand full of 

 big grains of starch, growing smaller towards the periphery, covered by a thick cuticule. 

 Nodes consist of small, thick-walled cells. Conceptacula unknown. Litharthron n. g. 



d. In the central strand all cells have almost the same dimension throughout the whole 

 joint. Nodes consist of one row of long cells. 



i. Joints cylindrical or broadened winglike; conceptacles form conical protuberances 

 on the joint Arthrocardia Aresch. 



2. Joints cylindrical or broadened winglike; conceptacles on the upper margin of the 

 broadened wing, immersed in the tissue of the joint . . Cheilosporum Aresch. 



3. Joints cylindrical or flattened; conceptacles at the growing top of the branches, 

 immersed in the tissue of the joint . . . Corallina Lamx. incl. yania Lamx. 



II. Fronds branched, articulated, cylindrical, calcified joints separated by calcified constrictions 

 of the frond. The joints consist of a central strand of long, undivided non-calcified filaments 

 standing in vertical rows with the calcified cells of the constrictions, and of a cortical layer 

 of calcified horizontally elongated cells. Conceptacula on the joints . . Lithothrix Gray. 



Amphiroa Lamx. 

 LAMOUROl \, Mémoire du Musée t. II, Paris 1812. Polyp. flexibles 1S16. 



The characters of the genera having been established I began the naming of the Amphiroqe 

 die Siboga collection and tried to find a character, that would help me to distinguish the 



