. Bulletins of American paleontology. 1(1 Bulletin 362 die Devonian in age. Centerfield and younger popu- lations (populations 3-10) are well dated within the Lower and Middle varcus conodont Zones and by def- inition are Givetian. The next older well-dated strati- graphic unit is the Cherry Valley Limestone within the kockelianus Zone in the upper Eifelian (Text-fig. 1). The Cherry Valley is below populations 1 and 2 leav- ing both as either late Eifelian or early Givetian in age. Klapper (1981. p. 61) suggested that the Mottville and higher members of the Skaneateles Formation could logicall
. Bulletins of American paleontology. 1(1 Bulletin 362 die Devonian in age. Centerfield and younger popu- lations (populations 3-10) are well dated within the Lower and Middle varcus conodont Zones and by def- inition are Givetian. The next older well-dated strati- graphic unit is the Cherry Valley Limestone within the kockelianus Zone in the upper Eifelian (Text-fig. 1). The Cherry Valley is below populations 1 and 2 leav- ing both as either late Eifelian or early Givetian in age. Klapper (1981. p. 61) suggested that the Mottville and higher members of the Skaneateles Formation could logically be assigned to the ensensis Zone on the basis of available conodont data. This would make our Case Hill population (2) early Givetian. Some workers have placed the base of the Givetian as low as the top of the Cherry Valley Limestone or within the overlying Chittenango Shale (see summary discussion of Kirch- gasser, 2000): either boundary would be below our Halihan Hill population (1). We conclude that the Halihan Hill and Case Hill populations (1, 2) are more likely early Givetian in age than late Eifelian, although the older one is very close to the boundary. The Centerfield and higher pop- ulations (3-10) are Givetian. BIOGEOGRAPHY The Early and Middle Devonian world was remark- ably provincial and corals were among the most pro- vincial of marine animals (Oliver, 1977, 1980. 1990; Oliver and Pedder, 1989). Three marine biogeographic realms are recognized: 1) the Eastern Americas Realm (EAR) included the North American Plate east of the Transcontinental Arch and south of the central Cana- dian Shield, and northern South America (with prin- cipal coral faunas in Venezuela and Colombia); 2) the Old World Realm (OWR) was much larger, including most of the rest of the world's rich coral faunas; and 3) the Malvinokaffric Realm included areas that were at a high Devonian southern latitude; the realm was coral poor, presumably because of cold water. Three Middle Devonian EAR prov
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