42 
F. O. BOWER. 
Not having the opportunity to make preparations from 
fresh materials, I was forced, in verifying these results, 
obtained with chromic acid materials, to use specimens pre- 
served in saturated solution of common salt, and afterwards 
hardened in alcohol. Sections from these, mounted in 
glycerine and acetic acid, gave the same results in all impor- 
tant points ; the distinction between the central column 
and the mucilaginous mass surrounding it being as distinct 
as in the chromic acid materials. When first mounted, 
however, in glycerine, the mucilage was marked by a very 
definite and beautiful system of striation and stratification ; 
this was more striking towards the periphery of the mass, 
towards the centre the marking gradually lost its regularity. 
After the sections had lain in glycerine for a short time the 
appearance faded and disappeared, probably owing to a 
gradual swelling. 
The direction of the systems is represented in fig. 7. In 
this figure it will be noticed that the outline of the cavity is 
irregular. This is due to the outgrowth of lumps of tissue, 
which, especially in male conceptacles, precede the formation 
of hairs. 
Here we come upon the first evidence of a sexual difference. 
The conceptacles have thus far, in the dioecious plant, 
offered no variety in development ,according as they are male 
or female ; but in the development and character of the 
hairs there is an appreciable difference. If the conceptacle 
be male the formation of hairs is preceded, as in fig. 7, by 
the outgrowth of irregular masses of tissue. The surface 
cells of these grow out into papillae, which divide and form 
hairs, these hairs branch according to a monopodial racemose 
system ; owing to their mode of origin these primary hairs 
are usually associated in bunches. 
If the conceptacle be female the hairs arise more uniformly 
over the inner surface of the conceptacle, and are, as a rule, 
not branched. It is only after these hairs have begun to be 
formed that the initial cell and central column are thrown 
off. Up to this stage it may, in thick sections, be almost 
always recognised. Though the central column is detached, 
still the conceptacle remains closed at the neck for some 
time longer. 
The antherida are not formed on the end of the upper 
branches of the primary hairs ; the lower lateral branches of 
them are, however, at an early stage terminated by antheri- 
dial cells. Antheridia are formed also on the apex of small 
hairs developed for that special purpose by the outgrowth of 
cells of the tissue lining the cavity, and these show, in its 
