IO NORTH AMERICAN ANOPLURA 



with well defined sternal plate. Legs all nearly of the same size, and 

 with a strongly chitinized skeletal piece between tibia and tarsus. Abdo- 

 men with a swollen, pad-like, strongly chitinized area on the lateral mar- 

 gin of the third to eighth segments. Tergites with many small, chitinized 

 plates or with none at all. Each tergite and sternite with one transverse 

 row of very small hairs. 



The genus is for the most part parasitic upon Ungulates. There are 

 but three species recorded from North America, all being from domestic 

 animals. 



Haematopinus asini (Linne). 



Numerous specimens from a horse, (Stanford University, Calif.) ; 

 also recorded by Osborn from horses. 



Haematopinus suis (Linne). 



Numerous specimens from a domestic hog, (Susanville, Lassen 

 county, Calif.) ; also recorded by Osborn from domestic hogs. 



Haematopinus eurysternus (Nitzsch). 

 Recorded by Osborn from domestic cattle. 



Linognathus Enderlein. 



Trichaulus Enderlein, Zool. Anz., vol. 28, pp. 139, 141, (1904). 



Linognathus Enderlein, ibid., vol. 29, p. 194, (1905). 



Linognathus Dalla Torre, Genera Insectorum, Anoplura, p. 12, (1908). 



Head more or less slender, without projecting temporal angles; an- 

 tennae five-segmented ; thorax small and elongated ; middle and poster- 

 ior pairs of legs nearly equal in size, larger and stouter than the anterior 

 pair. Abdomen entirely without chitinized tergal, sternal and pleural 

 plates ; the body-wall presenting a reticulated appearance. Each ab- 

 dominal segment with two or three transverse rows of rather long hairs. 



The species composing this genus are confined almost exclusively to 

 the Ungulata, one species, however, being recorded from the domestic 

 dog. But four species have been recorded from North America, and all 

 of these are found upon domestic animals. 



Linognathus vituli (Linne). 



Numerous males and females from cows (Mountain View, Santa 

 Clara county, Calif.). It has also been recorded by Osborn from cattle. 



