[12th October 1916] I observed two bees stationed at the aperture of the nest fanning with all their strength; no doubt they directed a current of fresh cool air into the interior of their tunnels. The bees post a sentinel at the nest aperture. The sentry is most earnest in its duty. It challenges each new arrival, possibly examines each burden as to its fitness for the store, or identifies each worker before it gives admission, in order to prevent the intrusion of a stranger. Sometimes, as though in doubt, it pursues a worker into the interior of the nest. It pays less attention to the departing bees; it seems to care little whether they leave empty or carry a little load of earth from the interior of the tunnel.
The resemblance of Fresh-water insects