DESCRIPTIONS AND DETERMINATIONS OF SPECIES II 



Linognathus stenopsis (Burm.). 



We have at hand several males and females, taken from a Mexican 

 goat (San Diego, Calif.), which we are referring to this species. It has 

 not previously been recorded from America. 



Linognathus piliferus (Burm.). 



We have a single specimen taken from a dog (Stanford University, 

 Calif.). It has been recorded by Osborn from a dog, but is apparently of 

 rather uncommon occurrence. 



Linognathus pedalis (Osborn). 



Haematopinus pedalis Osborn, Bui. 5, n. s., U. S. Dept. Agr., Div. Ent, pp. 170-172, 



fig. 99, (1896). 

 Trichaulus pedalis Enderlein, Zool. Anz., vol. 28, p. 142, (1904). 

 Linognathus pedalis Enderlein, Zool. Anz., vol. 29, p. 194, (1905). 



Recorded by Osborn as having been taken from the legs of a do- 

 mestic sheep at Ames, Iowa. 



Genus POLYPLAX Enderlein. 



Poiyplax Enderlein, Zool. Anz., vol. 28, pp. 139, 142, 223, (1904). 

 Polyplax Dalla Torre, Genera Insectorum, Anoplura, p. 13, (1908). 

 Haematopinus (Polyplax) Neumann, Archiv. de Parasit, vol. 13, pp. 529-532, (1909). 

 Polyplax Mjoberg, Arkiv. for Zoologi, vol, 6, no. 13, p. 159, (1910). 

 Polyplax Fahrenholz, Reprint from the second, third, and fourth Jahresberichte 

 des Niedersachsichen Zool. Vereins zu Hannover, pp. 29-30, (1912). 



Antennae five-segmented, the third segment in the male usually with 

 a pronounced pre-axial projection. Eyes lacking. Anterior pair of legs 

 small, middle and posterior pairs larger, posterior pair usually largest. 

 Abdomen with tergites and sternites well chitinized, and in certain seg- 

 ments transversely divided into two distinct plates ; the number of seg- 

 ments thus divided is not constant throughout the genus, and is always 

 less in the male than in the female. Each plate with a transverse row of 

 hairs ; pleural plates well developed, present on the first to eighth seg- 

 ments. 



The genus is composed entirely of species which find their hosts 

 among the Muridae. We are recording two species, one previously de- 

 scribed and one new, both from Murids. 



