I have been "bitten" on two separate occasions by ordinary-looking wasps. They seemed to drink some blood before flying away. Are there vampire wasps, or did they simply regard me as some sort of fruit?

If it happens again, catch the wasp and hold it in front of a mirror. If you can't see it, it's a vampire wasp. If you can, I'm afraid I don't know the answer.

GuyGr

Wasps are usually quite easy to identify. They have mandibles and could bite humans if they were interested, but they are not. They do not suck blood but feed on caterpillars and other insects. If humans get in their way they don't bite, they sting, and it is unimaginable that someone just having been stung can remain dispassionate and observe them in this manner.

Hoverflies mimic wasps, but being quite defenceless they are nigh impossible to approach. The most likely explanation of the behaviour described is the visit of a horsefly or cleg. These are bloodsucking flies best identified by their irridescent, rainbow-coloured eyes. They don't look much like wasps, but I suppose they could conceivably be mistaken for them. Clegs, also known as rain flies because they favour damp conditions, have a near-silent flight and are very adept at sneaking up unobserved on exposed skin. Like mosquitoes they inject a local anaesthetic before piercing the skin and proceeding to feed on the blood. They also inject an anticoagulant, because when swatted or driven away, the place where they have fed continues to bleed for a time. So not vampire wasps, but vampire flies.

Terence Hollingworth, Blagnac, France

Does the economy of the Monopoly boardgame resemble that of the real world?

It seems to me that Monopoly is exactly true to life, except that it's missing insurance.

pretendname

As far as some people ending up as paupers and others stinking rich, I'd say it is quite true to life.

smuglyfrombrazil

The thing about boardgames is that if you learn the rules and know how to bend them or work the weaknesses, you win. Life is a bit more complex as the rulebook is incomplete and different people have different versions.

epinoa

Monopoly is rubbish unless you play by house rules. Some people put their fines and fees on to the "free parking" square; I added a rule where at any point a player can decide they have had enough of the whole charade and start a communal urban farm with their neighbours, pursuing personal improvement and universal harmony rather than conspicuous consumption and a treadmill of crippling debt.

owenduffy

The economy of Monopoly resembles the real world in that I never have enough money in either.

David Sledge, Gerrards Cross, Bucks

It is not always understood by Monopoly players that the probability of landing on a particular square varies considerably over the board, due to the effect of the Go to Jail square and some of the Chance and Community Chest instructions. The fact that with two dice the most probable score is seven means that Park Lane is the least visited square and Trafalgar Square the most. Whether players can take any advantage from this esoteric knowledge is another question.

Gavin Ross, Harpenden, Herts

I am now 61. Should I continue to carry an organ donor card? If someone did want my organs, which would be the best bits left?

I would like to make it clear that, if you want to be certain that there is a record of your wish to donate your organs to save lives, you need to join the organ donor register (N&Q, 7 June). We can then check what you wanted, even if your donor card can't be found. It is also tremendously important to let your family and friends know of your decision so this doesn't come as a surprise to them. Sign up here.

Sally Johnson, NHS Blood and Transplant, Liverpool

Any answers?

Is it true that a student in a philosophy exam answered the question "Is this a question?" with "If that is a question, then this is an answer" and got top marks? Even if not, was the answer right?

Paul Caldwell, Beverley, East Yorks

Which cat did curiosity kill?

Dick Symonds, Broadstairs, Kent

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