This bibliography—the first of the kind hitherto published—deals with zoological and medical publications relating to the two species of lice (Pediculits humanus Linn. 1758 and Phthirus pubis Leach, 1815) infesting man, the part they play in pathology, the prophylactic measures and means of destruction employed against lice, their anatomy and biology and other matters pertaining to them.

The term Pediculosis denotes the pathological condition brought about by infestation with Pediculus humanus, either the head or the body or both of these being affected. Pediculosis may lead directly or indirectly to secondary infections of various kinds. P. humanus (corporis and capitis) has been shown to be the carrier of two important diseases affecting man, namely typhus and relapsing fever.

In the following account of the biology of Pediculus humanus, I have sought to bring together all that could be gathered from the publications of the many authors who have occupied themselves more or less with these insects, adding here and there my own observations2. I have sought throughout to give credit where it is due and have not withheld criticism where it appeared necessary.

The examination of a large number of individual lice in India, where the facilities for obtaining material are unusually good, has impressed me with the fact that the characters ordinarily given as differentiating corporis from capitis are all to a greater or less extent inconstant and unreliable. In general, however, capitis is more heavily chitinized and the chitin is of a darker colour with less smooth outlines. The size is very variable, but corporis has an easier life and is more often large.