47 2 Campbell . — Studies on some Javanese Anthocerotaceae. /. 
and not at all conspicuous, but may easily be demonstrated. Fig. 12 
shows a cell from the interior of the thallus of a form which was growing 
with the typical M. Tjibodensis. The specimens were not fertile, and 
no comparison could be made with the sporogonium of M. Tjibodensis , so 
that it was not possible to determine certainly whether it was specifically 
distinct, but the very different form of the chromatophores would indicate 
that it is a different species. There were seldom more than four chroma- 
tophores present even in the largest cells, and these were flattened and 
irregular in outline, and were more or less completely joined by fine 
protoplasmic filament, presenting a very different appearance from the 
small rounded and isolated chromatophores of the typical specimens. 
M. Salakensis differs a good deal from M. Tjibodensis in the character 
of the chromatophores. In the cells of the upper surface there is usually 
but a single chromatophore (Fig. 13), but this is often constricted, and may 
be completely divided into two. In the cells of the ventral surface two 
distinct chromatophores are generally present. These show a central area 
which is surrounded by numerous starch granules, and there are indications 
of a pyrenoid, but as we have seen, it is much less evident than in the 
typical Anthocerotaceae, where it is often very conspicuous. The cells 
below the epidermal layer contain usually two smaller chromatophores 
(Fig. j 5), which also show the pyrenoid-like centre body. The inner cells 
of the thallus (Figs. 16 and 17) contain from four to six small rounded 
chromatophores without any central body, which are connected by delicate 
protoplasmic threads into a sort of chain. 
Through the kindness of Dr. M. A. Howe, dried material of two 
species from tropical America was secured. An examination of these 
showed that they also possess multiple chromatophores. These were 
A. Vmcentianus , Lehm. and Lindenb., from Martinique, and A. jlavens, 
Spruce, from the Peruvian Andes. In both of these species (Figs. 18 and 
19) the inner cells contained two to four chromatophores, while the super- 
ficial cells had usually but a single one, although it was often deeply 
constricted, and occasionally divided completely in two. From this 
dried material it was not possible to make a study of the structure of the 
chromatophore beyond noting that apparently no pyrenoid was present, 
in which respect they seem to agree with M. Tjibodensis. 
While in most other Archegoniates the chromatophores are small and 
numerous, there are a number of exceptions which approach the condition 
found in Megaceros. The writer has found, as an exceptional occurrence, 
large flat chromatophores in the prothallial cells of Osmunda cinnamomea 
(Campbell, On the Prothallium and Embryo of Osmunda. Ann. of Bot., VI, 
1892), and in a species of Cyathodium collected in Java, apparently 
somewhat different from the common C. foetidissimum , the chromatophores 
were relatively very large, and in some cases there were only four in a cell. 
