Sweet

The bits of a flower that produce nectar are called, predictably, 'nectaries'. These seem to have evolved more than once since plants left the primordial oceans and colonised land - different plants have different structures in different places within the flower, using different physiological mechanisms to generate nectar. Most of them, though, have the same core purpose of attracting pollinators, so that the plant can cover them with pollen and send them on to the next flower to fertilise the ovum that it contains. (A few use nectar as bait to attract insects, trap and eat them, but insects would soon get wise if everyone did that)

There are such things as 'extrafloral nectaries': parts of a plant that exude nectar but are not part of a flower. These may simply attract insects to a plant, as a first step in guiding them to flowers, but they can also attract non-pollinating insects, such as ants, which then help the plant by removing aphids (or, more subtly, they might distract ants from finding sap-sucking aphids, which ants might otherwise protect and 'farm' - blackmail paid by plants to ants running a protection racket!) Bees are perfectly happy to take nectar from extrafloral nectaries, and indeed exudate from sap-sucking aphids - sugar is sugar, if you are a bee

Today, I have discovered there are also such things as 'pseudonectaries': structures that look like nectaries glistening with fresh nectar, but are in fact just plant tissue, with no reward for a visiting pollinator. You would have thought pollinators might regard this as a con, and shun these flowers in favour of some with a less twisted sense of humour. Apparently not: pseudonectaries are almost always accompanied by real nectaries. The latter may be somewhat hidden, so psedonectaries serve as an advertising hoarding - grabbing a pollinator's attention, and possibly also helping guide it to the actual meal; "Ed's Diner. 500 feet, look right". Some researchers also think pseudonectaries are a decoy - designed to distract undesirable visitors, but no hindrance to preferred pollinators, who are in on the subterfuge 

I knew I was taking a picture of Nigella damascena - 'love-in-a-mist' - one of the commonest, best-loved, old fashioned, cottage garden annuals. Only a bit of googling, trying to find out a bit more about it, brought to light that it has pseudonectaries, which of course caught my attention. The flowers and pseudonectaries are long gone; the green, bulbous seed-pod has dessicated, burst and spread its seed, the husk is now waiting for winter - perhaps storm Agnes will be the end of it tonight. For the moment, it still has a touch of sci-fi, other-worldly (can I say alien?) beauty to it, even on a grey day