6 
Introduction 
position of the bats. It becomes evident that bats are not evenly dis¬ 
tributed over the land areas of the earth. Of the seventeen families of 
Chiroptera, eight are confined to the old world, six are confined to the new 
world, and only three are common to both hemispheres. Moreover, of the 
three ubiquitous families, only the Vespertilionidae contains genera com¬ 
mon to both hemispheres and this common family has never been recorded 
as the host for any Polyctenid. Here, then, is a basis for the isolation of 
the old from the new world Polyctenidae. 
TABLE II 
Systematic Arrangement of the Hosts of Polyctenidae 
Old World 
Family Nycteridae (Hollow-faced Bats) 
Nycteris hispida Schreber 
Family Megadermidae (False vampire bats) 
Megaderma carimatae Miller 
Megaderma spasmae (Linnaeus) 
Megaderma s. ceylonicus Anderson 
Lyraderma lyra (Geoffroy) 
Family Rhinolophidae (Horse-shoe bats) 
Rhinolophus eloquens Anderson 
Family Emballonuridae (Sheath-tailed bats) 
TapJtozous cavaticus (Hollister) 
Taphozous perforalus Geoffroy 
Family Molossidae (Free-tailed bats) 
Nyctinomus cestonii (Savi) 
Mops thersites (Thomas) 
Family Pteropidae (Fruit-eating bats) 
Cynopterus brachyotis Muller 
Cynopteris marginatus Geoffroy 
New World 
Family Phyllostomidae (Leaf-nosed Bats) 
Artibeus perspicillatus Linnaeus 
Glossophaga longirostris Miller 
Family Molossidae (Free-tailed bats) 
Molossus cerastes Thomas 
Molossus fumarius Burmeister 
Molossus rufus Geoffroy 
Molossus perotis Wied. 
Molossus tropidorhynchus Gray 
Eumops abrasus (Temminck) 
Eumops californicus (Merriam) 
Eumops glaucinus Wagner 
Tadarida macrotis (Gray) 
Tadarida gracilis (Wagner) 
Origin and evolution of the Polyctenidae. Allen suggests that the center 
of distribution and perhaps the original home of the Chiroptera is the region 
surrounding the Indian Ocean. Ferris reached the same conclusion quite 
independently for the Nycteribiids and, as mentioned above, the most 
diverse and highly specialized Polyctenids occur in this region today. It 
would appear, then, that the primitive American Hesperoctenes became 
isolated from the main Polyctenid stock very early at a time when warmer 
temperatures permitted the Molossidae to migrate between the old and the 
new worlds. This route was later closed, leaving the American stock to 
develop its distinct but very closely allied species. Meanwhile, evolution 
was proceeding apace in the old world fauna with its potentialities for great 
diversity. Relatively primitive Hypoctenes and Adrodenes evolved a few 
special features in the Ethiopian Realm after which the widespread oriental 
genus Eoctenes invaded the Dark Continent. At least in the case of Polyc- 
tenes and Eoctenes , a wide variety of bat hosts were attacked, thus greatly 
facilitating their widespread distribution. 
