150 INSECTS AFFECTING DOMESTIC ANIMALS. 
twice 4; in posterior tarsi joint 1 equals 2 and 3 together, 5 a little longer than 3 
and less than one-half of 1, while 2 1s three times 4 and less than 4 and 5 together; 
hind femora with a row of bristles on the side; color, light reddish brown, darker 
dorsally on the abdomen; length, 2 to 2.5 mm. . 
Fic. 82.—Pulex bruneri: male—enlarged (original). 
While this species has been noted as so common on its ordinary hosts 
it has never been observed as occurring upon any of the domestic 
animals. 
THE DoG AND CAT FLEA. 
(Pulex serraticeps Gerv.) 
The common flea, affecting the dog and cat, was described by Duges! 
under the name of Pulex canis in 1852, and by Bouché? under the name 
of Pulex felis in 1835, these names referring to the forms infesting the 
dog and the cat, respectively. The reference of the two to one species 
under the above name by Gervais? was made in 1844. 
It is one of the most abundant species known, and is distributed 
practically over the entire world. Asa house pest it rivals the irritans, 
and in many places even seems to be about the only species occurring. 
Howard states that from the specimens sent to the Division of Ento- 
mology itis this species rather than irritans that is usually troublesome. 
It may be easily distinguished from that species by the presence of 
the combs of spines on the border of the head and pronotum, those on 
the head being usually 6 to 9 in number and those on the hind border 
of the pronotum 14 to 18 in number. 
The adults seem to adhere quite closely to their hosts, as cats and 
dogs infested by them will be found to carry them quite constantly, 
1 Ann. des Sciences Naturelles, Vol. XX VII, p. 157. 
?Nov. Act. Acad. Leop. Carol., Vol. XVII, i, p. 505. 
3 Hist. Nat. des Ins. Apt., Vol. III, p. 371. 
