A Swallow's Larder A completely persuasive account has been sent
me (by W. N.) of the so-described " wingless horse flies " found under the wing of a swallow. The description was roughly accurate, for though the creatures are parasites they are true flies that are either wingless or have lost the use of their wings ; and have therefore no biological relationship to " ticks." The parasites (which have no more simple name than hippoboscid ornithornvia croicularia!) are common on birds. They are pupiparous; that is, have the capacity of producing young at intervals in the form of grubs which go rapidly through the next two stages of change. The egg stage is omitted. All the group have specially adapted claws, used for clinging and making their way snugly into the protecting hairs or feathers. Most animals, birds, cattle, sheep and deer suffer from parasites of this group, and their geographical range is wide. Birds especially have distributed the race over a great part of the world.
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