In the systematic account which followed the above chapter in the 9th
edition of the _Encyclopaedia Britannica_, the following classification,
which is the same as that given in the author's _Introduction to the
Study of Fishes_ (London, 1880) was adopted by Albert Günther:--
Subclass I. : PALAEICHTHYES.
Order I. : _Chondropterygii._
With two suborders : Plagiostomata and Holocephala.
Order II. : _Ganoidei._
With eight suborders : Placodermi, Acanthodini, Dipnoi,
Chondrostei, Polypteroidei, Pycnodontoidei, Lepidosteoidei,
Amioidei.
Subclass II. : TELEOSTEI.
Order I. : _Acanthopterygii._
With the divisions Perciformes, Beryciformes, Kurtiformes,
Polynemiformes, Sciaeniformes, Xiphiiformes, Trichiuriformes,
Cotto-Scombriformes, Gobiiformes, Blenniformes, Mugiliformes,
Gastrosteiformes, Centrisciformes, Gobiesociformes, Channiformes,
Labyrinthibranchii, Lophotiformes, Taeniiformes and
Notacanthiformes.
Order II. : _Acanthopterygii Pharyngognathi._
Order III. : _Anacanthini._
With two divisions : Gadoidei and Pleuronectoidei.
Order IV. : _Physostomi._
Order V. : _Lophobranchii._
Order VI. : _Plectognathi._
Subclass III. : CYCLOSTOMATA.
Subclass IV. : LEPTOGARDII.
It was an artificial system, in which the most obvious relationships of
the higher groups were lost sight of, and the results of the already
fairly advanced study of the fossil forms to a great extent discarded.
This system gave rise to much adverse criticism; as T. H. Huxley
forcibly put it in a paper published soon after (1883), opposing the
division of the main groups into Palaeichthyes and Teleostei:
"Assuredly, if there is any such distinction to be drawn on the basis of
our present knowledge among the higher fishes, it is between the Ganoids
and the Plagiostomes, and not between the Ganoids and the Teleosteans";
at the same time expressing his conviction, "first, that there are no
two large groups of animals for which the evidence of a direct genetic
connexion is better than in the case of the Ganoids and the Teleosteans;
and secondly, that the proposal to separate the Elasmobranchii
(Chondropterygii of Günther), Ganoidei and Dipnoi of Müller into a group
apart from, and equivalent to, the Teleostei appears to be inconsistent
with the plainest relations of these fishes." This verdict has been
endorsed by all subsequent workers at the classification of fishes.
Günther's classification would have been vastly improved had he made
use of a contribution published as early as 1871, but not referred to by
him. As not even a passing allusion is made to it in the previous
chapter, we must retrace our steps to make good this striking omission.
Edward Drinker Cope (1840-1897) was a worker of great originality and
relentless energy, who, in the sixties of the last century, inspired by
the doctrine of evolution, was one of the first to apply its principles
to the classification of vertebrates. Equally versed in recent and
fossil zoology, and endowed with a marvellous gift, or "instinct" for
perceiving the relationship of animals, he has done a great deal for the
advance of our knowledge of mammals, reptiles and fishes. Although often
careless in the working out of details and occasionally a little too
bold in his deductions, Cope occupies a high rank among the zoologists
of the 19th century, and much of his work has stood the test of time.
The following was Cope's classification, 1871 (_Tr. Amer. Philos. Soc._
xiv. 449).
Subclass I. Holocephali.
" II. Selachii.
" III. Dipnoi.
" IV. Crossopterygia, with two orders: Haplistia and Cladistia.
" V. Actinopteri.