id 
tion, not having made a special investigation of what parts of the 
anther are really represented by the column and other processes. 
The very curious diaphragm which sepa. ates the two portions of the 
style is five-lobed, in consequence of a slight d. pression between the 
anthers, where, we may suppose, if fully developed, it would obstiuct 
the passage of an insevt’s proboscis throu zh the groove ; its lobes 
are in consequence opposite the anthers. From tue middle line of 
these lobes the glutinous secretions or glands arise, as may be seell 
more distinctly in the bud. They are, in th.s stage of the flower, 
the form of an inverted arrow head, the point being on the lobes just 
mentioned, and the barbs rising obliquely towards the openings for 
the polien. These barbs mature into the glutinous masses, ole 
from different pairs being on either side of the groove. The uppe 
part of the style, commonly considered the stigmatic surface, aud 
which is furnished with the glutinous processes, is of a firmer ¢ol 
sistency than the lower part, and, though pollen is often found om 
it uuder dissection, I have never found this pollen puttmg forth 
tubes. The part below the dissepiment is of a much looser texture, 
consisting mainly of curious oblong cells. Attached to the outside 
of this, just below the dissepiment, may often be found masses of 
pollen agglutinated together and protruding tubes in profusion, one 
tube from each of the four spherules of which the grain is com 
posed. These would be interesting objects for a microscopist. The 
tubes are parallel and very different in other respects, but, never 
theless, the object reminded me of the spores of Equisetum. oe 
Robevt Brown, it is well known, showed that this is the portion 
of the style in.Asclepias that is truly stigmatic, and succeeded 12 
tracing the tubes to the ovaries, the placentz, and finally the ovula 
Thave not succeeded in following them, far from it ; but I think 
it is clear that this is the true stigmatic surface in Apocynum also. 
_ The fly probably dips its head dowii to get at the nectaries in th 
bottom of the eup, and, in drawing it back, sometimes gets its pr? 
boscis caught in the groove between the anthers, to which 1} 
guided by their diverging bases. As the proboscis is drawn up th 
groove it passes the glutinous glands, which are easily detach 
when the flower is mature, and, being thus charged with one o 
both of these glands, draws out the pollen from one or both of t 
adjacent anther cells. Perhaps. alarmed by this rude entertainme!! 
the insect flies off to a more distant flower, where it goes throug! 
the same process, first, however, leaving the stranger pollen on thi 
stigmatic surface, Or it may, perhaps, sip about the same bus 
and being put on its guard, not be at once caught again in the sam 
trap. However this may he, it is evident that the whole wonderful 
contrivance is to prevent self-fertilization. Observers are mal 
_ indebted to Mr. Darwin for calling their attention to what prov 
_ be a very general and most curiously varied arrangement in flo 
_ to this one end. I might have mentioned that, where the filam 
bend closely along the base of the style, they are provided with 
- whether, as Sprengel would suggest, to protect the necta 
