lesser extent by all subsequent ichthyologists. For exam- 

 ple, Boulenger's "A Synopsis of Suborders and Families 

 of Teleostean Fishes" (1904a) and "Fishes, Systematic 

 Account of Teleostei" (1904b) followed Regan without 

 deviation, and Boulenger's (1907) only other interest in 

 plectognaths was his lateral view illustration of the 

 skeleton of the Nile puffer, Tetraodon fahaka (= 

 lineatus Linn.). 



On the other hand, Jordan (1905) accepted Regan's 

 work more critically, for while sparingly using Regan's 

 diagnoses, Jordan had his own ideas about the plectog- 

 nath subdivisions. For one thing, Jordan continued to 

 recognize three suborders of the Plectognathi, with the 

 Ostracodermi being one of them, rather than being 

 relegated, in Regan's fashion, to familial rank within the 

 Sclerodermi. Like Regan, Jordan (1905, 2:411) wished to 

 stress the close association of the plectognaths and 

 acanthurids, and did so by recognizing a "Series Plec- 

 tognathi" which is "derived directly from the Acan- 

 thuridae, from which they differ by progressive steps 

 of degeneration." But since the plectognaths "differ 

 from one another more widely than the highest or most 

 generalized forms differ from the Acanthuridae, we do 

 not regard it as a distinct order. The forms included in it 

 differ from the Acanthuridae much as the swordfishes 

 differ from ordinary mackerel" (Jordan 1905, 2:411). It is 

 a matter of opinion whether the magnitude of dif- 

 ference, external and internal, between such plectog- 

 naths as Mola and Triacanthus is of a higher degree 

 than that between the swordfish and mackerel, but in 

 any case Jordan was restating Dareste's acanthurid-plec- 

 tognath relationship. In Jordan's somewhat vague ter- 

 minology, the Chaetodontidae, Zanclidae, 

 Acanthuridae, and related forms comprised the 

 Squamipinnes, which gave rise to the Series Plectog- 

 nathi. But in 1898 Jordan and Evermann, in their "The 

 Fishes of North and Middle America" (part 2) made the 

 same point, the Plectognathi being called either an 

 "Order" (p. XVU) or a "Group" (p. 1696); and in 1923, 

 Jordan, in his "A Classification of Fishes," recognized an 

 Order Plectognathi with the following conservative sub- 

 groupings: 



Order Plectognathi 

 Suborder Sclerodermi 



fFamily Spinacanthidae [for all fossil triacanthoids] 



Family Triacanthidae 



Family Balistidae 



Family Monacanthidae 



Family Psilocephalidae 

 Suborder Ostracodermi 



Family Ostraciidae 

 Suborder Gymnodontes 



Family Triodontidae 



Family Tetraodontidae 



Family Canthigasteridae 



Family Diodontidae 



Family Molidae. 



Of more importance than the above classification were 



Jordan's collaborative reviews of various families of plec- 

 tognaths, making known many new species and rede- 

 scribing poorly known ones: Jordan and Edwards (1887); 

 Jordan and Snyder (1901); Jordan and Fowler (1903). Be- 

 fore continuing on to other researchers, it should be noted 

 that Jordan's belief in the close relationship of the plec- 

 tognaths and acanthurids was reinforced by the osteologi- 

 cal observations of his colleague Starks (1907:217) on the 

 Siganidae and Acanthuridae. 



An example of the combined effect that Woodward's 

 (1901) "Catalogue" and Jordan's numerous pub- 

 lications had on the subsequent handling of the plectog- 

 naths can be seen in Goodrich's (1909) "Cyclostomes 

 and Fishes." Woodward had used the Division 

 Chaetodontiformes for plectognaths, acanthurids, and 

 chaetodontids, while Jordan had stressed again and 

 again the close relationship of his "Series Plectognathi" 

 with his Squamipinnes. These messages were taken to 

 heart by Goodrich, for, even though he made free use of 

 Regan's osteological diagnostic information, he adopted 

 a modification of Woodward's and Jordan's views about 

 the placement of the Plectognathi. The eclectic result 

 was as follows: 



Subtribe Chaetodontiformes 

 (of the Tribe Perciformes) 



Division A, Squammipennes 

 Chaetodontidae 

 Drepanidae 

 Division B, Plectognathi 

 Subdivision A 

 Teuthididae 

 Siganidae 

 Acanthuridae 

 Subdivision B 

 Branch 1, Sclerodermi 

 Series 1 



Triacanthidae 

 Balistidae 

 Monacanthidae 

 Series 2 



Ostraciontidae 

 Branch 2, Triodontes 



Triodontidae 

 Branch 3, Gymnodontes 

 A 



Tetrodontidae 

 Diodontidae 

 B 



Molidae. 



Although the above "Plectognathi" was the logical ex- 

 tension of Jordan's championing of Dareste's ideas, it is 

 nevertheless the first time that the term Plectognathi 

 had included within its folds the acanthuridlike fishes. 

 More important, however, was the fact that the plectog- 

 naths proper (Subdivision B) were divided into three 

 major groups, one of which had never been recognized 

 previously at that level. The Triodontidae had formerly 



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