268 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



Brancbiostegi, Acanthopterygii, and Malacopterygii. The same arrangement 

 appears in bis edition of Artedi's work, 1 738, and iu subsequent editions of tbe 

 Systema up to and induding tbe seventb, 174S. His Cbondropterygii were 

 the genera Raia, Squalus, Acipenser, and Petromyzon. 



Gronow, 1754, following Linnc, recognized tbe horizontal-tailed fishes, the 

 Plagiuri, and tbe perpendicular-tailed fishes : the latter be subdivided into 

 those with bony-rayed fins, under the names ^lalacopterygii, Acanthopterygii, 

 and Brancbiostegi, and those with cartilaginous-rayed fins, the Chondrop- 

 terygii, which latter included the genera Callorhyncbus, Acipenser, Squalus, 

 Raia, and Petromyzon. He bad adopted most of his groups and genera from 

 Artedi and Linne : among tbe additions tbe jrenus Callorbvnchus is of most 

 present interest. It is from Gronow's band that that genus appears in the 

 ninth edition of the Systema, 175G, without mention of Chiraaera, though tbe 

 latter was established by Linne in 1754, two years before the publication of 

 that edition. 



Linne dropped tbe name Chondropterygii in the tenth edition of the Sys- 

 tema, 1758, for Amphibia nantes, and there tbe group contains Petromyzon, 

 Raia, Squalus, Chimaera, Lophius, and Acipenser. Callorhyncbus of Gronow, 

 1754, was buried in Chimaera of Linne, 1754. Tbe arrangement is similar in 

 tbe twelfth edition, with addition for the worse of Balistes, Ostracion, Tetro- 

 don, Diodon, Cyclopterus, Centriscus, Syngnatbus, and Pegasus. 



Gmelin, 1 788, in his edition of the Systema, returned to the name Chondrop- 

 terygii, and, dropping the name Amphibia nantes and taking out tbe genus 

 Lophius, constitutes the group as in tbe tenth edition with these exceptions. 

 Tbe other fishes, practically the bony fishes, be j)laced in tbe groups Apodes, 

 Jugulares, Thoracici, Abdominales, and Brancbiostegi. The group Chondrop- 

 terygii, with varying inclusiveness, has persisted. 



Cuvier, 1798, in the Tableau Elementaire, improved the arrangement by so 

 much as concerns the removal of Acipenser from the Chondropterygii, and by 

 retaining in the order Petromyzon, Raia, Squalus, and Chimaera His orders 

 were Les cliondroplerygiens, Les birinchiosteges, Les apodes, Les jugulaires, Les 

 thorachiques, and Les ahdominaux. This distribution with Latin names was 

 followed by Gravenhorst, 1807, who added to the Chondropterygii the genus 

 Gastrobranchus of Blocb, 1795, for Myxine glutinosa of Linne, 1754. 



La Cepede, 1798, divided the class into cartilaginous fishes and bony fishes. 

 He accepted the Chondropterygii of his predecessors, but wrongly included 

 various bony fishes, and though he carefully subdivided tbe groups he desig- 

 nated the minor divisions only by tbe names, apodes, jugulaires, thoracins, and 

 abdominaux in each case, repeating these names over and over again. 



Dumeril, 1806, in the Zoologie Analytique, gave French names, derived from 

 the Greek, to La Cepede's subdivisions. His first order of tbe cartilaginous 

 fishes was the Trematopnes, with two families, the Cyclostomes and tbe Pla- 

 giostomes. His second order, and third family, he named Chismopnes; its 

 contents were tbe so-called genera Baudroie, Lopbie, Baliste, and Chimere. 

 His third order, and fourth family, Eleutheropomes, included Polyodon, Aci- 



