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distinct the one from the other. But in Asclepiadaceae the whole of the 
sexual apparatus is consolidated into a single body, the centre of which is oc- 
cupied by a broad disk-like stigma, and the grains of pollen cohere in the 
shape of waxy bodies attached finally to the 5 corners of this stigma, to 
which they adhere by the intervention of peculiar glands. For a long time 
this structure was misunderstood ; but Brown, in a dissertation in the Trans- 
actions of the Wernerian Society, placed its true nature beyond doubt. I 
subjoin the explanation given by this celebrated botanist, who thus describes 
the fiower of Asclepias syriaca : — 
“ The flower-bud of this plant I first examined, while the unexpanded 
corolla was yet green and considerably shorter than the calyx. At this period 
the gland-like bodies which afterwards occupy the angles of the stamen were 
absolutely invisible ; the furrows of its angles were extremely slight, and, like 
the body of the stigma, green ; the antherse, however, were distinctly formed, 
easily separable from the stigma, and their cells, which were absolutely shut, 
were filled with a turbid fluid, the parts of which did not so cohere as to 
separate in a mass ; of the cuculli, which in the expanded flower are so 
remarkable, and constitute the essential character of the genus, there was no 
appearance. 
“ In the next stage submitted to examination, where the corolla nearly 
equalled the calyx in length, the gland-like bodies of the stigma were become 
visible, and consisted of 2 nearly filiform, light brown, parallel, contiguous, 
and membranaceous substances, secreted by the sides of the furrow, which was 
now somewhat deeper. Instead of the filiform processes, a gelatinous matter 
occupied an obliquely descending depression proceeding from towards the base 
of each side of the angular furrow. 
“ In a somewhat more advanced stage, the membranes which afterwards 
become glands of the stigma were found to be linear, closely approximated, 
and to adhere at their upper extremity. At the same time the gelatinous 
substance in the oblique depression had acquired a nearly membranaceous 
texture and a light brown colour ; and on separating the glands from its fur- 
row, which was then practicable, this membrane followed it. At this period, 
too, the contents of each cell of the anthera had acquired a certain degree of 
solidity, a determinate form, and were separable from the ceU in one mass ; 
the cuculli were also observable, but still very small and green, nearly scutelli- 
form, having a central papilla, the rudiment of the future horn-like process. 
Immediately previous to the bursting of the cells of the antherse, which takes 
place a little before the expansion of the corolla, the cuculli are completely 
formed, and between each, a pair of minute, light green, fleshy teeth are 
obsen^able, the single teeth of each pair being divided from each other by 
the descending alse of the antherse. The glands of the stigma have acquired 
a form between elliptical and rhomboidal, a cartilaginous texture, and a 
brownish black colour ; they are easily separable from the secreting furrow, 
and on their under surface there is no appearance of a suture, or any indica- 
tion of their having originally consisted of two distinct parts : along with 
them separate also the descending processes, which are compressed, mem- 
l)ranous, and light brown ;^their extremity, which is still unconnected, being 
more gelatinous, but not perceptibly thickened. The pollen has acquired 
the yellow colour, and the degree of consistence which it afterwards retains. 
On the bursting of the cells, the gelatinous extremity of each descending 
process becomes firmly united with the upper attenuated end of the corre • 
spending mass of pollen. The parts are then in that condition in wdiich they 
have been commonly examined, and are exhibited in the figures of Jacquin, 
who, having seen them only in this state, naturally considered these plants as 
tnily gynaridrous, regarding the masses of pollen as the antherse, originating 
