ANOPLURORUM BRITANNIA. 235 



T. Conspurcatum, are all good and characteristic marks. 

 In addition to the above, I have never found the latter 

 species either on a Duck or Merganser, nor this species 

 upon Swan or Goose. Mr. Thompson has sent me speci- 

 mens taken on the Wigeon (Mareca Penelope) and Golden- 

 Eye ( Clangula chrysophthalmos), from Belfast; Mr. Wallace 

 took it on the Pintail (Anas acuta) in the Isle of Man, and 

 my brother on the Teal (Anas crecca),the Goosander (Mer- 

 gus merganser), and the Smew (Mergus albellus), in Nor- 

 wich, and I believe Mr. Jenyns has found specimens on 

 the Red-breasted Merganser (Mergus serrator). From 

 the circumstance of its being found on three of our species 

 of Mergus, I should have considered it as the T. lituratum 

 of Nitzsch, which he says infests the Smew, but the specific 

 character as laid down by Dr. Burmeister would not warrant 

 such a conclusion. 



3. TRINOTON SQUALIDUM. Denny. (Louse of the Goose.) 



Plate XXII. Fig. 3. 



Pale yellowish-grey, shining and smooth ; head with 

 four black spots on the lateral margin ; thorax with black 

 fasciae ; femora with a black annulus at the apex ; abdomen 

 ovate. 



Head triangular, pale fulvous, with two semilunar 

 black spots on each side, bordered with chestnut, vertex 

 concave, base very broad and concave, with a transverse 

 black fascia ; eyes large ; antennae obscure ; prothorax large, 

 nearly as wide as the head, much contracted posteriorly, a 

 black band down each lateral margin ; mesothorax large, 

 lateral angles much produced and acute, posteriorly trun- 

 cate, a black transverse band in the centre, and two short 

 ones on the anterior margin ; metathorax transverse, with 

 a small black spot in the centre of the lateral margin, which 



