96 MR. Н. М. WARD ON THE STRUCTURE, DEVELOPMENT, 
the inner side (fig. 26), projecting slightly into the cavity of the cell. In some cases a 
definite faint stratification appears in the firm walls of these cells also. 
The apical cell of this series, as also those of the pedicels which spring from it and the 
ovoid bodies supported by them, all possess thinner and smooth cellulose walls. No 
definite nucleus has been discovered in any of these structures. 
In fig. 24 are drawn the various stages of development of the apical portion of a 
с fertile hair," after it has elongated, from a mere рарШозе projection of the thallus-cell, 
to nearly its full extent (figs. 15-21). The terminal cell of the primitively simple series 
(fig. 20) becomes swollen into a pyriform shape (fig. 24 а-с), from the upper portion of 
which are produced pairs of sacculations, which grow obliquely upward and outward, and 
become separated from the central body by simple septa (4-Ғ). Meanwhile the protoplasm 
containing oil and starch, which had previously become aggregated in large quantities 
in the apical cell, passing into these diverticula as they are formed, becomes finely 
granular, and collects at the free end of each pedicel, causing it in turn to swell up into 
a pear-shaped dilatation (fig. 247). Аз this increases in volume, and more and more 
fine-grained orange-coloured protoplasm, sap, &c. are poured in, it bulges outwards as 
an egg-shaped body, which may be termed a zoosporangium, and a septum commences 
to form, separating its cavity from that of the pedicel (fig. 24 e, &c.). This occurs 
in such a manner that the ovoid body becomes situated obliquely on the pedicel 
(еу. РІ. XX. figs. 28-31), the latter joining it at its lower third. 
From eight to twelve of these radiating pedicels &c. are commonly formed in succes- 
‘sion from one terminal or head cell of the “ Бал ;” and it follows from the mode of deve- 
lopment that successive pairs are younger than those preceding. It may, however, happen 
that, after producing a dozen or so of these bodies, the vigorous “ head-cell”’ grows for- 
ward and, after producing a short continuation of the main axis of the “ hair,” again 
commences to repeat the above-described phenomena : in fig. 22 the two tufts have arisen 
by this means. Іп other cases (especially, it would seem, after injury to the upper portion 
of the fertile hair) a diverticulum may arise from a lower cell, and form a lateral branch, 
which acts as if it were the main axis (fig. 23, а), and produces a terminal tuft of pedicel- 
late sporangia as before. Or the continuation of the vigorous axis may precede the 
formation of pedicels by the end cell (fig. 23,0). Finally, I have several times observed 
a branch springing from halfway down the main axis, and producing a normal tuft of 
pedicels and ovoid zoosporangia, the main axis at the same time bearing a completely 
developed tuft as above described: this case is a rarer one, however. In the typical 
example above described the end cell produces the pedicels and zoosporangia in pairs, 
more or less nearly at equal intervals ; abnormal cases occur, however, where one pedicel 
and its ovoid cell are formed long before others appear (figs. 28 с, 20, 21). 
The pedicels developed as lateral diverticula from the central head cell, and which pro- 
duce the large egg-shaped zoosporangia as described, soon become curved in a peculiar 
manner as the bodies which they support increase in size and, presumably, in weight. Each 
becomes partially doubled on itself from below, as if the weight of the zoosporangium had 
borne down the end: in consequence of this (figs. 29-32), the cell-wall of the lower side 
becomes tucked in as a double fold, partially shutting off the outer third of the cavity of the 
