130 



BOTANY 



PART I 



A. The median plane of all the lateral shoots may coincide with the median 

 plane of the lateral shoot of the first order. 



(a) The successive lateral branches are on the anterior side of the parent axis, 

 i.e. between the latter and the subtending leaf (cf. p. 121). In lateral view they 

 thus fall on the same side, DREPANIUM (Fig. 155 C, D). 



(/3) The successive axes stand on the posterior side of the parent axis (cf. p. 123) 

 and in lateral view appear alternately right and left, RHIPIDIUM (Fig. 155 A, B}. 



rir 

 A , 



^ 



FIG. 155. A, Rhipidium from the side ; B, rhipidium in ground plan ; C, dre- 

 panium from the side ; D, ground plan of drepanium ; E, ground plan of 

 dichasium (the red line indicates the mode of derivation of the cincinnus 

 and the blue line of the bostryx) ; F, ground plan of bostryx ; G, ground 

 plan of cincinnus. 1-9, successive, relatively main axes. In order to| make 

 the relations clearer the successive axes in A-D and F, G are indicated in 

 different colours. The subtending leaf borne by each axis has the same 

 colour as the axis from which it springs. (A-G, after EICHLER, the rest 

 modified from KARSTEN.) 



B. The median plane of each lateral shoot (of the 1st, 2nd, 3rd order, etc.) 

 is always transverse, i.e. right or left of the median plane of the subtending 

 leaf on the parent shoot. Such branch-systems can only be represented in ground 

 plan. 



(a) The successive lateral shoots are placed always to the same side, either to 

 the right or the left, BOSTRYX (Fig. 155 F). 



(]8) The successive lateral shoots stand alternately to the right or left, CINCINNUS 

 (Fig. 155 G, Fig. 154). 



