98 Campbell. — Studies 071 so7ne Java7iese Anthocerotaceae. II. 
as in Anthoceros. The small endothecium in this case was cut off by a 
periclinal wall. Fig. 38 shows a median longitudinal section of an 
older embryo in which the archesporium is completely differentiated. 
It agrees entirely with N. orbicularis in this respect; and as Mottier 
showed, the archesporium is of amphithedal origin and formed in exactly 
the same way as in Anthoceros. 
Cross-sections of embryos of about the same stage as that represented 
in Fig. 36, show much the same appearance as similar sections in the 
other genera, except that the columella is much less developed. While in 
Text-fig. i. Median longitudinal sections of embryos of about the same age, showing 
the extent of the archesporium in the four genera of Anthocerotaceae. A. Notothylas orbicularis ; 
B. Dendroceros Breutelii ; C. Megaceros tjibodensis ; D. Anthoceros Pearsoni. 
the larger sporogonia (Fig. 44) the columella may show three cells in 
longitudinal section, most of the smaller ones showed but four cells 
in cross- section, and it is less developed than in N. orbicularis . In some 
specimens but three cells were seen in cross-section (Fig. 42). This would 
indicate that the columella-cells were entirely suppressed in one of 
the quadrants of the embryo, and presumably in this quadrant the 
endothecium would contribute to the sporogenous tissue. In no specimens 
that were examined, however, was the columella entirely absent, and 
