There are almost 4,400 species of chewing lice in the world, the majority of which are found on birds. Each group of birds or mammals plays host to specific chewing lice, making lice ideal for helping determine the phylogenetic relationships of birds. This volume contains a key, broken down by host order, allowing ornithologists and bird lovers to quickly narrow down which group of lice might be present on a given bird. Beautifully detailed scientific illustrations of the more than 250 genera of chewing lice and lists of known hosts for each species provides the reader with a glimpse into this fascinating group. This book may be of interest to ornithologists, evolutionary biologists and of courses parasitologists.