1888. ] Mr J. R. Vaizey, On Splachnum luteum, Linn. 303 
is seen to be more particularly the case in the layers of cells next 
the foot. The foot itself is seen to consist of a cylindrical mass of 
parenchyma with an external layer of epidermal cells of a some- 
what columnar form, which contain a considerable quantity of 
protoplasm and contain large distinct nuclei. The protoplasm 
of these cells is found to be aggregated towards the external 
surface, the nucleus being usually found in the peripheral mass 
of protoplasm ; a thin layer of protoplasm is formed all round the 
other walls of these cells and large vacuoles are present which are 
traversed by fine protoplasmic filaments. There are in these cells 
a great number of small round protoplasmic bodies, especially — 
ageregated round the nucleus and towards the peripheral side of 
the epidermal cells, which appear to be a kind of plastid. As 
plastids are usually employed in some absorptive and assimilative 
process I would suggest that in this case the plastids are engaged 
in the process of absorbing nutriment for the sporophyte from the 
tissues of the oophyte. 
In the centre of the foot there is a definite central strand 
consisting of two kinds of tissue, an outer layer of cells containing 
protoplasm, the leptophloém* surrounding an inner strand of 
more thin-walled cells containing no protoplasm, the leptoxylem. 
The leptophloém cells have their protoplasm aggregated towards 
the periphery like the epidermal cells, but differ from them in 
that they contain no plastids. The leptoxylem I have proved’ 
in other species of Splachnwm to be the tissue by means of which 
water is conveyed up the seta to the apophysis. 
The seta has a distinct epidermis, beneath which there is a 
layer of sclerotic supporting tissue and parenchyma; this paren- 
chyma together with the sclerotic tissue forms the cortex. In the 
centre is the central strand which in the lower part has almost the 
same structure as that above described in the foot, except that it is 
larger and is less distinctly delimited from the surrounding tissue. 
Higher up in the seta the centre of the leptoxylem is occupied by 
a large intercellular space which forms an intercellular passage 
for nearly the whole length of the seta. This intercellular space 
is lysigenous in origin. A similar passage or canal is found in 
several other species. 
A longitudinal median section through the umbrella- -shaped 
apophysis shews that the “central strand” here swells out mto 
a large pear-shaped mass of cells which in the mature sporophyte 
contain no protoplasm, and in the younger states only a very small 
quantity with small inconspicuous nuclei. Chlorophyll bodies are 
absent except in the two outermost layers of cells, even in the 
youngest specimens observed, and here there are only a very few ; 
the cells are all thin walled and cubical in shape, without any 
1 Cf. Vaizey, loc. cit. for definition of the terms leptophloém and leptoxylem. 
2 Vaizey, Note on the Transpiration of the Sporophore of the Musci. Annals 
of Botany, vol. I. 
22—2 
