Lewisi 'in a' louse (Haematopinus) is, in its main features, similar.
That a wood-louse and a land-crab are alike Malacostracans, and that they have by different paths alike become adapted to terrestrial life, are facts which even a philosopher might condescend to notice.
Two species of Pediculus are found on the human body, and are known ordinarily as the head-louse (P. capitis) and the body-louse (P. vestimenti); P. capitis is found on the head, especially of children.
The louse of monkeys is now generally considered as forming a separate genus (Pedicinus), but the greater part of those infesting domestic and wild quadrupeds are mostly grouped in the large genus Haematopinus, and very rarely is the same species found on different kinds of animals.
The name was first given in 1834 to a plant-louse which was observed to "dry up the leaves" of oaks in Provence.