ANOPLURORUM BRITANNIA. 223 



* * Abdomen rotundate. 



9. MENOPON MESOLEUCUM. (Louse of the Rook and 

 Hooded Crow.) 

 Plate XX. Fig. 2. 



Pale testaceous and pubescent ; head sub-conical, with 

 four pitchy black spots ; abdomen with darker bands. 



Menopon mesoleucum. Nitzsch. Germ. Mag. iii. p. 300. Steph. Cat. pt. 

 ii. p. 334. Burmeister Handbuch ii. pt. ii. p. 439. Ricinus cornicis. 

 De Geer, vii. p. 76. tab. 4. fig. ii. (pupa). Nirmus cornicis. Latr. G. 

 i. 169 ? Samou. Ent. Com. U3 ? 



Head sub-conical, vertex concave ; clypeus with a pitchy 

 spot on each lateral margin, two large spots before the eyes ; 

 occiput slightly concave ; eyes fuscous ; prothorax nearly 

 as wide as the head, semicircular, with a depressed marginal 

 line, and a transverse one in front ; metathorax transverse, 

 sub-conical; abdomen obtusely ovate with fuscous bands, 

 sutural margins pale testaceous ; legs thick and strong ; 

 anterior femur the largest, somewhat spoon-shaped, superior 

 margin involute. Length \ to f . 



A common parasite on the Rook (Corvus frugilegus), and 

 Carrion Crow (Corvus corone), frequenting the base of the 

 beak, and the orbital region. With the exception of the 

 RASORIAL, perhaps no birds are so much infested with 

 Nirmi as the Corvidce, and yet in none of these that I am 

 aware, is the peculiarity of a pectinated claw found, which 

 has been conjectured to be a provision for assisting the Birds 

 so provided, to cleanse themselves from their parasites.* 

 Whatever the use of such claws may be, I cannot think it is 

 solely for the above purpose ; for this reason, that of all the 

 Nirmi, the genera Lipeurus Colpocephalum, and Menopon, 

 adhere the closest to the feathers, and consequently all 

 Birds infested with any of these, ought of all others to be so 



* Professor Owen, Cyclopaedia of Anatomy and Physiology, article 

 "Aves,"pt. iv. p. 349. 



