atum described and figured by NıengurG (1908 Taf. VII). Like these it lacks the 
regular apical cell-divisions characteristic of the older shoots of the Phycodrys-plants; 
the monostromatic frond is composed of uniform cells which are rather irregularly 
divided, intercalary divisions being very frequent, and no mid-rib is present. Our 
sporeling differs, however, from those described by NIENBURG in being erect, while 
the latter, according to the said author, are decumbent, growing along the sub- 
stratum (l. c. p. 185). This primary. shoot has been found again in a number of older 
plantlets collected in July; it 
had reached a considerable 
size, up to 6 mm long and 
2 mm broad or more, and had 
a broadly lanceolate shape, but 
otherwise showed the same 
character as before. It was thor- 
oughly monostromatic, com- 
posed of uniform, irregularly 
disposed cells becoming small- 
er upwards, and terminated 
in an apical cell divided by 
transversal walls, but showed 
no trace of a mid-rib. The 
base of the primary shoot was 
contracted in a short stalk 
fixed to the substratum by a 
basal disc. From the stalk one Fig. 434. 
or more adventitious shoots Phycodrys rubens. A, plantlet found in July in the Little Bell on Sertu- 
ae? 5 R laria, with lobed primary frond; atthe base a young adventitious shoot. 
showing the typical apical 20:1. B, tip of the primary frond in A, showing the apical cell. 260 :1. 
growth and a well developed 
mid-rib were given off; the mid-rib could be traced to the very base (fig. 433 B). 
The primary frond in an advanced stage terminates in an apical cell dividing 
like that of the typical fronds, and the first divisions of the primary segments are 
similar to those mentioned above of the normal fronds, but intercalary divisions 
occur early and continue in still greater number than in the ordinary leaves and 
cause the arrangement of the cells to become much more irregular than in these 
(fig. 434 B). The cells in the middle of the frond do not show any tendency to longi- 
tudinal arrangement and no divisions parallel to the surface of the frond occur. 
Secondary apical cells appear and may give rise to slight sinuosities of the outline 
(fig. 434 A above) but normally they do not occasion branching. Primary fronds 
with one lateral lobe such as that represented in fig. 434 may, however, sometimes be 
met with. Even in these fronds no rudiment of a mid-rib was discernible. The prim- 
ary fronds thus agree perfectly well with the normal fronds in Nilophyllum (comp. 
NIENBURG 1908). The discovery of the primary frond in Phycodrys rubens is in good 
60* 
