12 The Ganoids 
Ganoids. They all have, for example, (1) the paraglenal ele- 
ments undivided (not disintegrated into hypercoracoid, hypo- 
coracoid, and mesocoracoid; (2) a humerus (simple or divided, 
that is, differentiated into metapterygium and mesopterygium) ; 
and (3) those with ossified skeletons agree in the greater number 
of elements in the lower jaw. Therefore, until these coordi- 
nates fail, it seems advisable to recognize the Ganoids as con- 
stituents of a natural series; and especially on account of the 
superior taxonomic value of modifications of the brain and 
heart in other classes of vertebrates, for the same reason, and 
to keep prominently before the mind the characters in question, 
it appears also advisable to designate the series, until further 
discovery, as a subclass. 
“But it is quite possible that among some of the generalized 
Teleosts at least traces of some of the characters now consid- 
ered to be peculiar to the Ganoids may be discovered. In 
anticipation of such a possibility, the author had at first dis- 
carded the subclass, recognizing the group only as one of 
the ‘superorders’ of the Teleostomes, but reconsideration 
convinces him of the propriety of classification representing 
known facts and legitimate inferences rather than too much 
anticipation. 
“It is remembered that all characters are liable to fail with 
increasing knowledge, and the distinctness of groups are but 
little more than the expressions of our want of knowledge of 
the intermediate forms; it may in truth be said that ability 
to segregate a class into well-defined groups is in ratio to our 
ignorance of all the terms,” 
