2 6o 
Pr anker d. — On the Structure and Biology of 
Schizaea sp., only that it is median and connected with many leaf-gaps 
instead of with one. 
In general, the anatomy of the two species is similar, but at the base 
of the inflorescence in Hottonia inflata some variations are found owing to 
the fact that the vascular structure of the branches is here that of the aerial, 
and not, as in Hottonia palustris , the aquatic type. As the transitional 
region is reached, the separate V-shaped bundles of the main inflorescence 
approximate and fuse into an incomplete ring, the same thing taking place 
in the lateral inflorescences at a somewhat higher level (Text-fig. 5). 
The separate pieces of the lateral branch traces tend to curve in horse- 
shoe fashion as in the main stem of H. palustris , the endodermis always 
Text-fig, 4. Longitudinal section of stem near the base of the inflorescence, x 20. 
(Diagrammatic.) 
running round the incurved edges. The smaller of these meristeles 
sometimes form completely concentric structures — the xylem phloem, 
pericycle, and endodermis all fusing adaxially and enclosing a central mass 
of ground tissue (PL XX, Fig. 2). 
Not one of the three specimens at my disposal showed any approach 
to this phenomenon in the main stem, hence (if these were typical) while 
H. palustris shows a phase of polystely where the constituent steles are 
imperfect, H. inflata exhibits the more complete type of individual stele. 
The mode of insertion of the lateral upon the main stele varies greatly : 
in general, the upper branch traces enter the main vascular ring in several 
pieces (Text-fig. 5, b), while the lower unite as single concentric structures 
(dr. 4'). In the latter case the subtending leaf-trace is completely fused with 
the branch trace ; in the former it frequently unites with a portion of the 
lateral trace (dr. 2), or may remain entirely separate till the trace has 
