482 Campbell. — Studies on some Javanese Anthocerotaceae . /. 
side of the thallus. This is less marked in M. Salakensis. In this species 
also many rhizoids are formed immediately below the sporophyte. These 
are presumably concerned in supplying the growing sporophyte with water 
and possibly with food. It would not be surprising if sometimes the 
rhizoid-like outgrowths of the foot itself might penetrate into the substra- 
tum, but no demonstration of this could be made. The spores of both 
of the species of Megaceros under consideration are small — much smaller 
than in most species of the other genera. The contrast is especially great 
when compared with the large spores of Dendroceros with which Megaceros 
otherwise most nearly agrees in the character of the sporophyte, as well 
as in the thin walls and green chromatophore of the spores. In both species 
examined the ripe spore contains a bright green chromatophore and germi- 
nates very promptly. In size the spores are about equal in the two species, 
measuring about 28 //, in diameter. Those of M. Tjibodensis (Figs. 66 , 6 9) 
are less regular in outline than those of M. Salakensis (Figs. 73, 75), and 
the surface papillae are coarser and less uniform in size. The elaters of the 
two species also differ, as we have seen, those of M. Tjibodensis being rather 
more slender and more seldom branched. They may reach a length of 
300 [jl, or more, and are usually composed of about three cells, although 
small unicellular ones (Fig. 68) are sometimes found. In M. Salakensis 
the elaters are almost always markedly branched, and the ends of the 
branches are often blunt, showing where they have broken away from 
others, and indicating clearly that the elater is only a part of an extensive 
net of sterile cells surrounding the spores (Figs. 71, 72). 
Germination. 
Experiments were made in germinating the spores of M . Tjibodensis. 
The spores germinate promptly, the first signs of germination being usually 
evident within two days. Within three days the first cell division occurs. 
Most of the cells of the young plant have a single chromatophore, but 
occasionally two are found in a cell. No germ tube is found, and the 
young thallus develops directly from the spore. The first rhizoid is formed 
earlier than is usually the case in A nthoceros. 
The Relation of Megaceros to the other Anthocerotaceae. 
Megaceros shows points of contact with all three of the other genera. 
The form of the thallus (at least in the species under consideration) is that 
of a typical A nthoceros, and this is true also of the apical growth which, 
however, resembles also that of Notothylas. The archegonium is perhaps 
most like that of Dendroceros , and this is true also of the large solitary 
antheridium. The sporophyte resembles most nearly in form and in its 
large size A nthoceros, but in the early divisions of the embryo and the 
