396 THE ANIMAL PARASITES OF MAN 



2. Pediculus vestimenti, Nitzsch, 1818. 



The head in front is somewhat rounded. Antennae longer than 

 in the head louse ; 2 3-5 4 mm. in length ; whitish-grey ; the 

 abdomen is broader than the thorax ; stigmata as in P. capitis. 

 Eggs 0*7 0'9 mm. in length ; about seventy are deposited. 



Pediculus vestimenti lives on the neck, throat and trunk of persons, 

 and the clothing next the body, in which also the eggs are deposited. The 

 louse of so-called pedicular disease (Pediculus tabescentium] is, according to 

 Landois' researches, only the usual Pediculus vestimenti ; moreover, many 

 cases of phthiriasis are attributable to mites or fly maggots. 



[This parasite has often been a great pest amongst soldiers during long 

 campaigns, especially amongst the Russians during the Crimean War. 

 F. V. T.] 



3. Phthirius inguinalis, Redi, 1668. 

 Syn. : Pediculis pubis, L. 



Male 0-8 ro mm. in length ; female ri2 mm. in length ; colour 

 greyish-white ; form sub-quadrate ; the two posterior pairs of legs 

 are strong ; the abdomen has nine segments and six pairs of 

 stigmata ; and still another pair of stigmata is situated between 



Fig. 255. Phthirius inguinalis, Leach (enlarged). They are distinguished by the 

 larger tracheal trunks originating from the stigmata. 



the two anterior limbs. Eggs pear-shaped, O'8 0*9 mm. in length, 

 0*4 o'5 mm. in breadth, and are deposited in rows of about ten 

 on the hairs. 



Pediculus pubis, which is found almost exclusively in the Caucasian 

 race, lives on hairy parts of the body, but hardly ever on the skin 

 of the head ; the pubic region is its favourite place of abode. 1 



1 Literature of the Pediculida. Landois, L., " Unters. ub. d. a. d. Mensch. schma- 

 rotzend. Pediculinen " (Z. /. w, Z., 1864, xiv.-xv., p. i ; 1865, pp. 32 and 494). Graber, 

 V., " An.-phys. Stud, uber Phthirius inguinalis" (ibid., 1872, xxii., p. 157). Giebel, 

 C. G., " Insecta epizoa, Lpzg., 1874. Piaget, E., Les p6diculines. Leide, 1880; Suppl 

 Letde, 1885. Artauld de Vevey, St., " Deux cas de pediculose accid. et intermitt. chez 

 I'komme " (C. R. soc. biol., Paris, 1895, No. 29, p. 684). 



