COMOSÆ, in Botany, from Coma; an order of plants in the former edition of Linnæus's Fragments of a Natural Method, consisting of the spiked willow or spiræa frutex, dropwort, and greater meadow-sweet. These, though formerly distinct genera, are by Linnæus collected into one, under the name of spiræa. The flowers growing in a head resemble a bush, or tuft of hair, which probably gave rise to the epithet Comosæ.