Career
He is credited with the discovery of Galanthus ×allenii (1883). Allen spotted Galanthus ×allenii amongst a batch of bulbs that had been imported from the Caucasus. Originally classed as a species, this strongly scented snowdrop is now thought to be a hybrid.
lieutenant is described as being "intermediate in appearance between G. caucasicus and G. ikariae", and may be a natural hybrid between those species.
