55 
style, or stigmata separate, and curve backwards, and the 
anthers that surround them retire and shrivel up, after 
having lost all their pollen; but at the same time the pollen 
which was deposited on the outside of the style, detaches 
itself, and the hairs that covered the surface disappear. 
««'This led Cassini to call these hairs deciduous, and to 
say that they disappear at the same time with the pollen 
which they retained. 'There then remains, he says, upon the 
style, nothing more than little asperities." 
M. Alphonse DeCandolle is yet more explicit. He 
expresses himself thus, “the arms of the style begin to di- 
verge. Atthe same time the pollen disappears, the collecting 
hairs drop off, and the style becomes altogether smooth.” 
Nevertheless a microscopical examination of these hairs 
has satisfied me that they do not fall off, but that they offer 
a phenomenon of which I know no other example in the vege- 
table kingdom. They are retractile like the hairs of certain 
Annelids, or the tentacula of snails. 
If we examine a thin longitudinal slice of a young style, 
before the emission of the pollen, it is seen that these cylin- 
drical hairs, a little tapering to their fine extremity, are formed 
by an external lengthening of the epidermis, and that they 
are perfectly simple, without articulation or partitions even at 
their base. 
Immediately below the base of each hair, there exists in 
the subjacent cellular tissue a cavity about equal in depth to 
half or a third the length of the hair, continuous with its 
cavity, and apparently filled with the same fluid. This 
cavity however does not extend beyond the most superficial 
stratum of the style or stigma, and has no relation to the 
tissues situated deeper, of which mention will be made pre- 
sently. 
d his arrangement is preserved up to the time of the ex- 
pansion of the flower, the hairs being at that time covered by 
grains of pollen, applied over their surface, and held between 
their interstices. = 
But at this period the hairs return into the cavities formed 
at their base among the cellular tissue ; the terminal half 
ensheathes itself in the half situated next the base, as it by 
degrees is returned into the cavity. The point only of the 
hair remains projecting beyond the surface of the style, and 
causes the asperities noticed by Cassini. Sometimes the hair, 
