ANOPLURORUM BRITANNIA. 9 



the internal edge : unguis large, thick, reflexed towards 

 the tooth near the apex of the tibia, from which several 

 bristles arise, which enables the animal to adhere with 

 greater pertinacity to the surface upon which it is 

 moving. 



1. PHTHIRIUS INGUINALIS. (Crab Louse.) 



Plate XXVI. Fig. 3. 



Body dirty yellow-white, beautifully chagreened with 

 minute papillae ; abdomen somewhat quadrate ; thorax with 

 a dark patch on each side, encircling the spiracle ; legs pale, 

 fulvous; ungues chestnut. Length $ , 5 1. 



* 



Pht. inguinalis. Leach, Zool. Misc. iii. p. 65. Leach, Ediub. Ency. ix. 

 p. 77. Leach, Ency. Brit. Supp. i. pi. 24. Samou. Ent. Comp. p. 142. 

 Burmeister, Hand Ent. i. pt. 1. p. 58. Burmeister, Gen. Insect. 

 Rhyn. Step. Cat. pt. ii. p. 329. Pediculus inguinalis. Redi Exper. 

 pi. 19. Pediculus pubis. Linn. Syst. Nat. ii. p. 1017. Faun. Suec. 

 1940. Fab. Ent. Syst. iv. p. 418. Syst. Antl. 341-3. Nitzsch. Germ. 

 Mag. iii. p. 305. Berk. Syn. i. p. 170. Stew. ii. p. 297. Turt. iii. 695. 

 Albin. Spi. pi. 49. fig. sinist. Pou du pubis. Latr. Hist. Nat. d. Crus. 

 et d. Inst. viii. p. 94. Le Morpion. Geoff. Hist, des Inst. ii. p. 597. 

 Pou du pubis. Lam. Animaux San. Ver. t. 5. p. 50-3. 



Only one species of this genus is known ; which infests 

 the pubic region generally of persons of dissolute habits. 

 It however occasionally spreads over other parts of the 

 body. Instances are known, though very rarely, of its ap- 

 pearing upon individuals whose habits are quite the reverse. 

 Specimens of this species were forwarded to me by a physi- 

 cian of the highest respectability in the south of England, 



* The measurements adopted in this work refer to a line and its 

 fractions. 



