128 MONOGRAPH I A 



Gull (Larus ridibundis) through Mr. Thompson of Belfast, 

 and from the Common Tern (Sterna Hirundo) through Rev. 

 L. Jenyns. 



21. NIRMUS VANELLI Denny. (Louse of the 

 Gray Plover.) 



Plate VII. Fig. 6. 



Pale, testaceous, smooth and shining ; head elongate and 

 conical, with a dark interrupted lateral margin ; abdomen 

 with oblique pitchy fasciae on the sides. 



Head large, elongate, and conical, sinuated on each side 

 b fore the eyes, with a series of pitchy spots on the lateral 

 margin, forming a somewhat interrupted band, base rotun- 

 date ; trabeculae short and acute ; antennae long and slender ; 

 prothorax transverse; metathorax with a dark humeral patch 

 on each side, posterior margin angular ; abdomen elongate, 

 sub-claviform, with a series of oblique pitchy fascise on the 

 lateral margin of the segments, and a short transverse, fus- 

 cous spot in the centre of each segment, underside of the 

 abdomen with a large oblong fuscous patch ; legs thick, 

 pale yellow ; the anterior femora large and rotundate ; tarsi 

 chestnut. Length ^ i 5 f . 



Communicated from the Gray Plover (Vanellus griseus), 

 by Mr. Thompson ; and from the Turnstone ( Strepsilas 

 interpres), by Mr. Tweedy. 



22. NIRMUS MERULENSIS. Denny. (Louse of the 

 Blackbird.) 



Plate VII. Fig. \. 



White, smooth, and shining ; lateral margin of the abdo- 

 men chestnut, with angular black mark ; head and thorax 

 bright yellow. 



