Ksw. Campbell et al., ON THE NOMENCLATURE OF THE ROOFING AND CHEEK BONES IN PRIMITIVE DIPNOANS, Journal of vertebrate paleontology, 15(1), 1995, pp. 28-36
An attempt is made to examine the problem of the nomenclature of the r
oofing bones in the most primitive dipnoans, which is still a matter o
f contention. The letter and number system that has been in use for th
e last half century was based on Dipterus, a Middle Devonian genus tha
t has a reduced number of bones and a greatly shortened cheek in compa
rison with the Early Devonian Dipnorhynchus. Several attempts have bee
n made to expand the Dipterus nomenclature to accommodate the more pri
mitive condition in Dipnorhynchus and Uranolophus, but none has yet be
en generally accepted. The most recent attempt by Westoll (1989), whic
h involves errors of reconstruction and interpretation, is discussed i
n this paper. The matter is of importance because assessment of the re
lationships of primitive dipnoans to other groups depends to a substan
tial extent upon these homologies.