26 
LOUSE OF THE WHITE FOOTED MOUSE. 
(Hematopinus hesperomydis, n. sp.) 
d Body elongate, general color golden yellow. 
al ee 4 , Female.—Head subquadrate, rounded in front, a concavity 
é »_g for the rostrum, obtusely angulated on the posterior border; 
a ‘qy antenne set near the front; first joint large, short; second 
V Cc : pas longest, the rest nearly equal; fourth with a small tooth on 
oe ae ae, , the posterior border, terminal pit with several short hairs. 
Thorax shorter than the head, small, sternal plate cuneiform, 
obtusely angular, irregularly or obliquely truncate in front and 
sharply pointed behind; anterior legs small and weak, the 
middle ones somewhat larger, the posterior pair much the 
largest, flattened; terminal joint of tarsus very broad and 
curved, opposing basal joint of tarsus and meeting tibial spur 
in such manner that the three form almost a complete eylin- 
Fic. 14. Hematopinus ger; abdomen oval elongate, sparsely set with short spiny 
hesperomydis —a, dorsal ; 3 : 
SE aaa hairs, one or two long hairs at lateral angles of sixth and 
view ; 6, head; ec, sternal =) 
plate; d, posterior leg; e, Seventh segments. 
terminal segments, male; Male, more slender, head longer and tapering somewhat 
all enlarged. (Original.) toward the front. See Fig. 14. 
Egg, as seen in the body of adult female specimen, is elongate oval. 
Millimetres. 
IDOMNGHH NS Aor Sao dnampoanesod GqeSEn anc bdeeadiquad qusgicébe .75 to .90 
WiGthir en eee see oes Fe ee cnt PE eS tse ae ge 28 to .33 
Head: 
IDES e 3 S655 besnos 650 Sapooe Boao sase cabese copa tssaS ¢ 13 to .16 
AV VER CG ee ts en Se Ope ate ace on aa aren epeietoee oe rerete 10 
Thorax : 
Wien Ob Meee tee seiciain stsele Aac.e ees Saige seeiserers seeees 10 
AV Val ibe Aras Sees eo Sooo aes oe es She ee ee eae 13 to .15 
Abdomen : 
IL GW eon ponsnos coserbsocediseoood Seo5 SbG000a4 ac0r .50 to .60 
B10 (i) eee ee een ert | eee a eee er Oo See. C 28 to .33 
The species approaches the acanthopus, resembling it in the form of 
the sternal plate, the character of the legs, and the general form ofthe 
body. It differs, however, in having the sternal plate less narrowed 
posteriorly, more obtuse, or even truncated in front; more decidedly 
still in the form of the head, which is longer and less excavated for the 
insertion of the antenne. It is also smaller, and the egg, if we may 
judge by what we can see through the walls of the female, is more 
elongated. 
It has been collected from the white-footed or deer mouse, Hesperomys 
leweopus, at Ames, Iowa. 
ee eer eee re 
