2 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 120 
Kellogg, 1908, and M. lophocerus Bedford, 1920. Hopkins and Clay 
(1952) included in the genus Chapinia the additional species, Colpo- 
cephalum hirtum Rudow, 1866, Menopon acutovulvatum Piaget, 1881, 
and Allomenopon mjébergi Eichler, 1947, but they considered the 
generic position of C. hirtum doubtful. In the present study C. 
hirtum is shown to be a Chapinia, and a neotype is designated; 
A. mpébergi is shown to be a synonym of M. acutovulvatum. Hopkins 
(1941) designated a lectotype for Chapinia lophocerus (Bedford), 
Clay (1949a) designated a lectotype for C. acutovulvata (Piaget), and 
a lectotype is designated here for C. bucerotis (Kellogg). Piaget 
(1880) identified a female from hyticeros cassidix (Temminck, 1823) 
as C. hirtum, but Piaget’s specimen is shown here to be the new species 
Chapinia lydae. The genus Bucerophagus was described by Bedford 
(1929) for his species B. africanus and for Colpocephalum productum 
Burmeister, 1838. For the latter species a neotype was erected by 
Conci (1950), and a lectotype was designated by Clay (1951a). 
Hichler (1947) described a new genus for Menopon forcipatum Nitzsch, 
1874, but Hopkins and Clay (1952) put MZ. forcipatum in the genus 
Bucerophagus. A neotype for B. forcipatus (Nitzsch) is designated 
here from Eichler’s material. Clay (1951la) stated that Bucerophagus 
africanus and B. productus both infest the two hosts, Bucorvus abys- 
sinicus (Boddaert, 1783) and B. leadbeateri (Vigors, 1825). No 
morphological or statistical means were found in the present study 
to separate the populations of each species on each host so that only 
the two species, Bucerophagus productus and B. africanus, could be 
recognized. 
The phylogenetic arrangement of the hornbills (Peters, 1945) 
shows scant regard for the geographical regions, and the list winds 
back and forth between the Ethiopian, Oriental, and Australasian 
regions (table 13). The mallophagan genera studied here, however, 
fall into definite species-groups confined to the Ethiopian region or to 
the Oriental and Australasian regions. It is believed, therefore, that 
the arrangement of the Mallophaga gives more insight into the origin 
of the hornbills than study of the host skins. 
Classification of the hosts is that proposed by Deignan (1963) 
except for species not discussed by him, for which Peters (1945) has 
been followed. Skins of the hosts collected in Thailand are in the 
U.S. National Museum and were identified by Mr. H. G. Deignan. 
Collections were made possible by assistance from the U.S. Operations 
Mission to Thailand and the U.S. National Museum. 
Grateful appreciation is expressed to Dr. Cluff E. Hopla, Oklahoma 
University, Dr. K. C. Emerson (KCE), Stillwater, Okla., and Dr. 
Theresa Clay, British Museum (Natural History) (BMNH), for 
their many suggestions and constant help; to Dr. Clay for the loan 
