112 OUTLINES OF ENTOMOLOGY. 



when the insect is feeding, are thrust into the skin to support the 

 lancets. The eyes are simple and very small, and the antennae very 

 short and minutely bristly. The legs have thick, short, notched joints 

 and end in a strong curved claw, that when closed down, meets a little 

 tooth on the shank — a provision for clinging to and climbing hairs. 

 There are no transformations. The eggs are called "nits," and are 

 firmly glued at one end to the hairs. 



Three species attack man under certain external conditions of pov- 

 erty and uQcleanliness, namely: The Head-louse {Pediculus capitis), 

 which is confined to the hair and skin of the head, and is most frequently 

 found on neglected children ; the Body-louse {Pediculus vestmenta), 

 which hides in the seams and folds of the clothing, and draws the blood 

 from any part of the body ; and the Crab-louse {Pthirius pubis), which 

 attacks the arm pits and pubic region. These pests commonly aggra- 

 vate the miseries of military prisons and camps and other situations 

 where human beings are congregated without provision for cleanliness 

 and lack nourishing food. Mercurial ointment is the best remedy, with 

 entire change of clothing, where possible. 



The true lice that are sometimes found on thin and neglected 

 horses, cattle, swine and other animals, differ very slightly from those 

 found on man. They are placed in the genus Hematopinus. Strong 

 infusions of tobacco or of larkspur seeds are among the remedial 

 washes, also an ointment of kerosene and lard, thoroughly mixed ; but 

 the experiments of Prof. C. P. Gillette, of Colorado, have demonstrated 

 the superiority of that valuable insecticide, the ordinary kerosene emul- 

 sion, over every other preparation, in ridding animals of these pests. 

 Dr. Riley, whose invention it was, says of it : "It has long since be- 

 come recognized as an insecticide of unrivaled merit, against most of 

 the insect enemies of plants, and also in the case of animals, as a means 

 against the Buffalo-gnat, Horsefly, etc. * * * The only precaution 

 necessary with this substance is to see that the emulsion is properly 

 made, and that in winter time the animal be protected from severe 

 cold." 



There are certain other kinds of lice occasionally found on cattle, 

 belonging to the same group with chicken-lice, bird-lice and so forth, 

 which, although they bear considerable resemblance to the true lice, 

 are structurally very different and form a low sub-order of the Xeu- 

 roptera. The remedies for these are the same as for the more common 

 species. 



