Page:The American Cyclopædia (1879) Volume IX.djvu/168

 160 ICHTHYOLOGY nffius, bringing back the amphibia nantes, how- ever, into the class of fishes, and dividing them, with Artedi, into branchiostegi and chondropte- rygii. Comparative anatomy had made con- siderable progress toward the end of the 18th century, when Lac6pede began his researches (1798-1803). He divides the class into cartila- ginous and osseous fishes, in each of which subclasses he makes four divisions: 1, with neither opercula nor branchial membrane; 2, without opercula, and with a branchial mem- brane ; 3, with opercula and without branchial membrane; and 4, with both opercula and branchial membrane. In each of the eight di- visions he adopts the orders of apodes, jtigu- lares, thoraciei, and abdominales, according to the absence of ventrals, or their position on the throat, thorax, or abdomen. The natural history of fishes in Sonnini's Buff on (1803-'4) is essentially a copy of Lac6p6de without ac- knowledgment. These works of Bloch and LacSpe'de supplied the principal foundation for most subsequent systems. The classifica- tion of M. Dum6ril, in his Zoologie analytique (1806), resembles that of LacdpSde, inasmuch as it lays stress upon the supposed absence of opercula and branchial rays and the position of the ventrals. Pallas, in the third volume of the Zoographia Busso-Asiatica (1811), gives a list of 240 species, distributed into 38 genera, with the exception of three taken from Linnteus; he makes two orders, spiraculata or chondro- pterygians, and branchiata, forming with rep- tiles (pulmonata) the class monocardia (single- hearted or cold-blooded animals). In 1815 Rafinesque published a second ichthyological system in his " Analysis of Nature, or Tableau of the Universe " (1 vol. 8vo, Palermo) ; though containing many errors, this system is valuable for several true affinities between fishes before and since regarded as widely separated, as for instance that of the polypterus with the stur- geon family. De Blainville in 1816 (Journal de Physique, vol. Ixxxiii.) published a classifi- cation in which fishes are divided into gnatho- dontes or osseous and dermodontes or cartilagi- nous, the latter distinguished by having teeth adherent only to the skin ; the former include the heterodermes or branchiostegi, and the squammodermes or common fishes; in the subdivisions the Linncean character of the posi- tion of the ventrals is adopted, and the families are established principally on the form of the body; it does not employ the Lacdpedean characters taken from the opercula and bran- chial rays. Cuvier in 1817, in his Begne ani- mal, divides fishes into chondropterygian and osseous. The former contain the families of suckers (lampreys), selachians (sharks and rays), with fixed branchiaa, and the sturionians (sturgeons), with free branchise. In the osse- ous fishes he suppresses the branchiostegi, form- ing of a portion of them the order plectognathi, from a peculiar mode of articulation of the jaws, including the families gymnodonts, scle- roderms, and lophobranchs. The remaining osseous fishes he separates into the orders maja- copterygians and acanthopterygians, after Ar- tedi, according as the rays of the dorsal fin are soft or spiny. The soft-rayed order he dis- tributes into families according to the Linnrean method of the position of the ventrals, disre- garding entirely characters drawn from the opercula and branchial rays. The spiny-rayed fishes form a single order, with the families tsenioids (ribbon fishes), gobioids (blennies and gobies), labroids (bass), percoids (perches, a very extensive family), scomberoids (mackerel- like, also numerous), squammipennes (chreto- dons, &c.), and the flute-mouths (fistularia, &c.). lie thus makes in all 22 families, found- ed on direct observation and comparison, and not simply compiled from previous authorities. Goldfuss ("Manual of Zoology"), in 1820, adopted the four orders of Gmelin, giving to them Greek names, and subdividing them into four families, each according to the shape of the head, mouth, or body, or other external character. Thus far the systems have been little more than repetitions of the combinations of Artedi, Linnseus, and Lacdpede. Compara- tive and philosophical anatomy began to be studied with zeal from the beginning of the 19th century. Oken, Cams, Geoffrey Saint- Ililaire, Spix, Weber, Van der Hoeven, Meckel, Everard Home, Hunter, Tiedemann, and others, wrote upon different portions of the structure of fishes, and the results of their studies began to modify ichthyological classifications. Be- fore mentioning the anatomical and embryo- logical systems, the classification adopted in the Histoire naturelle dei poissons, by Cuvier and Valenciennes, beginning in 1828 and com- ing down to 1868, may be alluded to. In this, fishes are divided into osseous and cartilagi- nous, the latter (or chondropterygians) inclu- ding the families sturionians, plagiostomes, and cyclostomes. The osseous fishes have the branchiae pectinated or laminated, with the exception of the lophobranchs, which have them in the form of tufts ; all the acanthopte- rygians have the upper jaw free, including 13 families, and all themalacopterygians except the scleroderms, gymnodonts, and lophobranchs; the malac'opterygians are divided into abdomi- nals, subbrachians, and apodes. Cuvier had very abundant materials at his command, em- bracing the collections of P6ron, and those of the expeditions under Baudin, Freycinet, Du- perrey, Dumont d'Urville, and other French naval officers. Oken, in his " Physiophiloso- phy " (Ray society edition), calls the class glos- sozoa, as those animals in which a true tongue makes its appearance for the first time, and os- teozoa, because in them also the bony system first appears. He makes four divisions, the cartilaginous and apodal jugulares, thoraciei, and abdominales, the first two having an irregu- lar and the last two a regular body. Among the systems based upon that of Cuvier are those of Bonaparte, Swainson, Straus-Durck- heim, and Rymer Jones. The classification of