TRICHODECTIDM. 



383 



CASE Ornithobius cygni {Linn.). — 54. Specimens ; 55. Enlarged figure of ditto; 

 "^Nos^' ^®' Illustrative vignette (whistling sw^an). 



54-56. ^ ^ , 



Infests the swan. 



(^^S£ Sub-family Trichodectid^. 



XIX 



This sub-family differs from the other Mallo- 

 phaga or bird-Hce, in attacking mammals. Its 

 species are all restricted to them, as all the 

 other genera of the Mallophaga are to birds. 

 It contains only two genera, Trichodectes (the 

 form found in Britain), and Gyropus, which is omithobiur cygni (from the 

 found on the sloth and cavies (South American 

 mammals). 



Genus Trichodectes. 

 Antennae three-jointed, and tarsi with only one claw. 



Nop. Trichodectes similis {Dewiy). — 1. Specimens; 2. Enlarged figure of 

 ^' ditto ; 3. Illustrative vignette (red deer). 



Infests the red deer. 



Nos. Trichodectes longicornis {Nitzsch).—^. Specimens (4); 5. Enlarged figure 

 -^~^- of ditto; 6. Illustrative vignette (fallow deer). 



Not uncommon on the fallow deer, and found in greatest 



numbers on the inner side of the thigh. 



^^ Trichodectes sph^rocephalus {Mizsch). — 7. Specimens ; 8. Enlarged 

 figure of ditto ; 9. Illustrative vignette (sheep). 



Trichodectes sphaerocephalus (from the sheep). 

 2 of a-line in lengtli. 



Found on sheep ; not common. 



Posterior leg of ditto. 



