THE LIMITS OF THE CLASS OF FISHES. 73 
Linné first, in the tenth edition of his “Systema Nature’? 
(1758), eliminated the cetaceans from the class of fishes and 
combined them with the viviparous quadrupeds in a single class, 
for which he proposed the now universally accepted name Mam- 
malia. At the same time that he eliminated the cetaceans, how- 
ever, he violently divorced from the class of fishes and referred to the 
amphibia, under the name Amphibia nantes, first (in 1758), all the 
Chondropterygii of Artedi (except thé sturgeons) as well as the 
genus Lophius ; and, subsequently (1766), he removed still others 
from the class, completing the removal of the Chondropterygii by 
the exclusion of the sturgeons, and discharging at the same time 
the genera Cyclopterus, Balistes, Ostracion, Tetrodon, Diodon, 
Centriscus, Syngnathus and Pegasus, most of which formed the 
Branchiostegi of Artedi. He seems to have been led to this 
measure by the belief that they were provided with lungs instead 
of gills, apparently having been misled by an erroneous observa- 
tion of Dr. Garden, of Charleston, on Tetrodon. 
Gmelin, in his edition of the “Systema Nature” (1788), re- 
stored to the class the forms thus divorced from the fishes. 
The genus Myxine was referred to the class Vermes by Linné 
and his followers, and therefore doubtless was overlooked by Bloch, 
who redescribed it as a fish under the name Gastrobranchus. 
The constituents of the class having been at length, for the 
time, agreed upon, the question of its subdivision or union with 
others was next agitated. 
Pallas combined the fishes with the Amphibia of Linné in a 
class, codrdinate with mammals and birds, which he named Mono- 
cardia. Long afterwards, Prof. Owen adopted the same view, but 
_ gave the new name Hematocrya. 
On the other hand, the elder Geoffroy St.-Hilaire, and following 
him, Latreille,* separated the combined Elasmobranchiates and 
Marsipobranchiates as a class (equivalent to the order Spiracu- 
lata of Pallas), and named it Ichthyoderes or Ichthyodera. This 
view, however, fell still-born. ee 
In 1856, Prince Charles Bonaparte + recalled that Isidore Geof- 2 
* LATREILLE (Pierre André)—Familles Naturelles du Règne Kiting; exposées 
succinctement et dans un Apa analytique avec Pindication de leurs genres. Paris, 
J. B. Baillière. Libraire de Bandouin Frères. 1825. [8vo, 570 pp-]—Troisième Classe, 
ayeee Airie (G. St. H.), p. 107; qne Classe, Poissons, Pisces. 
p. 1 
t Bien (Prince Charles eas Be Tableaux paral- 
léliques de la deuxième sous-classe bar Oien Præcoces ou Autophages;. . . 
