8 ART. 14.— K. YENDO: 



When the articuli at the basal portion grow in thickness, after 

 they have been geniculated, the consequence is that they always 

 assume a moniliform shape : and if the growth of the diameter of the 

 genicula has corresponded to that of the articuli, we have a homo- 

 geneous cylinder with parallel rings at certain distances. In the 

 former case the result is always " linear " in form, as in Amp. aberrans, 

 Cor. officinalis and many others : in the latter case " bandform " 

 genicula are formed, as in Amp. dilatata, Amp. ephedrœa, &c. 



At the upper portions of the fronds we find several differences 

 in the position of the genicula. These various positions may be 

 divided into two, the normal and the abnormal. 



A. The Xormal Position. 



The normal position of genicula is always at the ends of the 

 articuli, situated in the direction of the rachis. This position is 

 most common in the members of the Corallinœ. And the genicula 

 belonging to the axial stem or to the main branches are of this type. 



There might be two equal or several unequal genicula at the 

 distal end of an articulus. In the former case the two genicula are 

 mostly separated in the meridional plane. This results in the 

 branching mode which I have called the " direct " dichotomy 

 (fig. F). In some dichotomous fronds, a single geniculum is on the 

 top of each arm of Y-shaped articuli, instead of two genicula at the 

 diverging point, forming the branching mode which I have called 

 " indirect " dichotomy (fig. (J). In Cor. decussato-dichotoma and its 

 allied species, the two genicula are situated, side by side, at the top 

 of an articulus. But the partition plane of both genicula is always 



]) Yendo: Cor. verœ Japon, p. 10. footnote. 



