NO. 3558 MALLOPHAGA—ELBEL 9 
Abdominal tergites each with a posterior marginal row of setae, the 
most laterad being the postspiracular seta. Each lateral margin of 
abdominal tergites II-VI with or without a short seta between the 
spiracle and postspiracular seta. Sternites and pleurites each with a 
posterior marginal row of long setae and with numerous shorter setae. 
Male terminal abdominal sternites VIII and IX fused with partial 
division only from sternite VII (figs. 4, 10, 22, 24, 26). Male genitalia 
as illustrated for each species, with parameres either expanded an- 
teriorly or split posteriorly or both. Female terminal abdominal 
segments as illustrated for each species, with lateral processes arising 
from ventral sclerite between vulva and anus, with long stout setae 
but never strong spines. Females larger than males, usually with 
more abdominal sternal setae, but general shape and chaetotaxy 
similar to that of males except for terminal abdominal segments. 
Both Ewing (1927) and Bedford (1930) stated that the ptero- 
thorax was undivided. As noted by Cope (1941), the sclerotized 
median button behind the prothorax (fig. 25m) is a vestige of the 
mesonotum; the supposed mesonotum, the narrow sclerotized band 
posterior to this button, is a mere extension of the subcoxae. Ewing 
(1927) stated that the abdomen consisted of 9 segments in the female 
and 10 segments in the male, but as shown by Cope (1941), 
the abdomen of both the male and female has 10 segments each. 
Chapinia resembles most closely Bucerophagus (figs. 66-69) but 
differs in several characters: The terminal segment of the antenna 
shows no sign of division in Chapinia, but there are definite signs of 
division into two parts either by transverse line or marginal indenta- 
tion in Bucerophagus. The venter of the third femora may have 
brushes of normal setae in Chapinia and Bucerophagus; similar brushes 
are present on posterolateral margins of abdominal sternites [V-VI 
in Chapinia but abdominal sternites 1V and V in Bucerophagus. Each 
lateral margin of abdominal tergites JI-VI may have a short seta 
between the spiracle and postspiracular seta in Chapinia, but 1-5 
short setae may be present on margins of abdominal tergites II-VIII 
in Bucerophagus. Male terminal abdominal sternites VIII and IX 
are fused in Chapinia with partial division only from abdominal 
sternite VII, but abdominal sternites VIII and IX may be fused in 
Bucerophagus with a complete division from abdominal sternite VII. 
Male genitalia have parameres slender or expanded anteriorly in 
Chapinia but branched anteriorly in Bucerophagus. Lateral processes 
arising from the ventral sclerite between the female vulva and anus 
have long stout setae in Chapinia but long stout setae and strong 
spines in Bucerophagus. 
The male genitalia and details of the male and female terminal 
abdominal segments are the best characters for separating species 
