68 
A. E. GIBBS—NOTES ON MOSSES. 
allies, the lichens, to clothe them with a delicately-tinted vesture, 
thus beautifying what has been forsaken by man. Mosses are to be 
found both on the mountain and in the bog; many species, such as the 
Orthotricha , grow on trees, while some, like many of the Splachna , 
are to be found only on the exuviae of herbivorous and carnivorous 
animals. As in the case of the higher plants, different species 
occur on the outcrops of different geological formations. Thus on a 
steep chalk cutting or cliff we may look for Seligeria calcaria, while 
S. recurvata prefers sandstone rocks. The rare S. paucifolia , which 
is recorded from but few localities, but which we had the good 
fortune to find in the Tunnel Woods last autumn, grows on detached 
chalk nodules partly buried in the soil. The Sphagna which form the 
greater portion of the peat in peat bogs, are a very interesting genus, 
but unfortunately are not very largely represented in our county, a 
fact due doubtless to the very little bog-land to be found in Hert¬ 
fordshire, and which through drainage is yearly becoming less. I 
have only discovered Sphagnum subsecundum and one or two of its 
varieties in the neighbourhood of St. Albans. The Phasca mostly 
affect fallow fields, the Grimmice dry rocks and walls, while a 
Hypnum may be found almost anywhere. 
Mosses, it need scarcely be said, are Cryptogams, but they belong 
to the higher and more-developed division of that class. All plants 
lower than mosses are thallophytes, that is to say, they have no 
distinct leaf and stem, but, like the algae, fungi, and lichens, have 
the two combined in a cellular, filamentous or flattened leafy expan¬ 
sion. But when we get so high in the scale of vegetation as the 
Musci, we find that Nature has taken a new departure, and we get 
the two great groups of organs—the foliar and the axial. Hoot, 
stem, and leaves are present, and in the wonderful contrivances for 
their fertilisation we get the key to the plan adopted by Nature in 
the more fully developed Phanerogamia. “ There is nothing,” says 
the Rev. Hugh Macmillan,*' “in the appearance or structure of 
the lichens, fungi, or algae, to remind the popular mind of higher 
plants; they form, as it were, a strange microcosm of their own—a 
perfectly distinct and peculiar order of vegetable existence. But 
when we ascend a step higher and come to the mosses, we find for 
the first time the rudimental characters and distinctions of root, 
stems, branches, and leaves — we recognise an ideal example of 
the flowering plants, all of whose parts and organs are, as it 
were, sketched out in anticipation, in these simple and tiny 
organisms.” The stem in some of the mosses is very rudi¬ 
mentary, as in the Seligeriece , while in others, as in the 
Polytricheacese, it is strongly developed. As the mosses are the 
lowest plants producing a true stem-axis distinct from the leaves, it 
is to be expected that the histology of the stem would be very 
simple. It consists, according to Bentley, wholly of parenchyma, 
with occasionally a central cord of liber cells, but no true vessels.f 
Sachs, however, says that in mosses with string-like formations in 
* 1 First Forms of Vegetation,’ 2nd ed., p. 22. 
f ‘ Manual of Botany,’ p. 91. 
