Comparative morphological and palynological studies have been carried out on Plantago fastigiata (P. insularis) of the New World and P. ovata, including some closely allied species of section Leucopsyllium, of the Old World. As a result, P. fastigiata is regarded as conspecific with P. ovata. It is postulated that the North American populations known as P. fastigiata are introductions of P. ovata dating from the late 18th and the beginning of the 19th century by early settlers in California.