Poissons Cartilagineux, while the other plectognaths 

 were in the first order (Apodes) of the fourth division, 

 well separated from the balistoids. 



When one considers the "Poissons Cartilagineux" as a 

 whole, the plectognaths were associated with much the 

 same genera as they were in Gmelin's 13th edition (1788) 

 of the "Systema Naturae." Again, just as in Gmelin, 

 Batistes was separated from the other plectognaths, 

 although in a more definite manner. One innovation was 

 Lacepede's handling of the plectognath genera. His con- 

 temporaries had accepted four genera {Balistes, Ostra- 

 cion. Tetrodon, and Diodon) but Lacepede admitted six 

 (Balistes, Ostracion, Tetrodon, Les Ovoides, Diodon, 

 and Les Spheroides). It happened that his two new 

 genera were based on artifacts or misinformation and 

 thus lost their value, except for nomenclatural purposes. 

 Les Ovoides (Lacepede 1798:520) was based on a damag- 

 ed specimen described by Commerson which lacked dor- 

 sal, caudal, and anal fins. Lacepede had never seen the 

 single specimen used by Commerson but thought that it 

 probably represented a new genus, and so named it. Les 

 Spheroides (Lacepede 1800:22) was likewise said to lack 

 dorsal, anal, and caudal fins. It was based on an unpub- 

 lished figure by Plumier of the anterior view of the body 

 of what we know now as Sphoeroides spengleri. Lacepede 

 did somewhat better with his other genera, for each of 

 these was divided into unnamed subgenera. 



Balistes (Lacepede 1798:332) contained four sub- 

 genera; the first for those forms with more than one spine 

 in both the pelvic and first dorsal fins; the second for 

 those with more than one spine in the pelvic fin but only 

 one spine in the first dorsal fin; the third for those with 

 only one spine in the pelvic fin but more than one spine 

 in the first dorsal fin; the last for those with but a single 

 spine in both the pelvic fin and first dorsal fin. 



The first subgenus should only contain triacanthoids, 

 which by common definition are those plectognaths with 

 well-developed pelvic spines. Lacepede mistook the en- 

 larged scales that occur in the midventral line of the ab- 

 dominal region of many balistoids between the end of the 

 pelvis and the anus for pelvic fin spines. These scales 

 strengthen the "abdominal fan" of those balistoids 

 whose pelvis is especially movable around its anterior ar- 

 ticulation with the pectoral girdle. The distal ends of the 

 enlarged scales are tapered into narrow shafts which 

 often project out through the skin on either side of the 

 midventral line (see Monod 1959a), and it is not sur- 

 prising that they should have been considered to be 

 some kind of pelvic fin spines. Lacepede also observed 

 the thickened scales that encase the posterior end of the 

 pelvis and mostly obscure from view the modified fin-ray 

 element of most balistoids, and understandably thought 

 them also to be a pelvic fin spine, as had others before 

 him and afterward (e.g., Garman 1891). For these 

 reasons Lacepede's first subgenus contained not only the 

 single binomially described triacanthid then known but 

 also three balistids. His second subgenus contained a 

 single monacanthid, whose modified scales in the ab- 

 dominal fan were again mistaken for pelvic fin spines. 

 The third subgenus was by far the largest of his sub- 



genera, containing numerous balistids and a few 

 monacanthids. The fourth subgenus contained two 

 monacanthids. 



Intervening between the descriptions of Balistes and 

 the next group of plectognaths {Ostracion) were the 

 descriptions of Chimaera, Polyodon, and Acipenser. 

 Ostracion (Lacepede 1798:441) was divided into four sub- 

 genera on the basis of the four logical combination pos- 

 sibilities of the presence, or absence, of cuirass spines in 

 the ocular region and of the presence, or absence, of 

 cuirass spines in the caudal region. These categories are 

 superficial and have not withstood the test of time. 

 Tetrodon (Lacepede 1798:474) had three subgenera, of 

 which the first two were described as not having the body 

 particularly compressed and consisted of tetraodontids, 

 while the third subgenus was said to have a compressed 

 body and contained a single molid. Diodon (Lacepede 

 1800:1) had no subgenera and contained four diodontids 

 as well as two molids, one of which was the same species 

 that also occurred in the third subgenus of Tetrodon. 



Lacepede's only subgeneric groups of lasting value 

 were those of Balistes, which have since, at least in part, 

 been elevated to familial rank. His contribution to the 

 plectognaths was primarily the recognition of the fact 

 that the Linnaean genera could, and should, be sub- 

 divided. His subgenera tended to be arbitrarily drawn 

 and factual errors pervaded his descriptions, but he 

 began the trend of subdivision of the Linnaean categories 

 of plectognaths. 



Like that of Lacepede, the classification adopted by 

 Bloch and Schneider (1801) in their "Systema Ich- 

 thyologiae" was deductively logical and equally ar- 

 tificial. Eleven classes of fishes were recognized on the 

 basis of the number of fins, i.e., Hendecapterygii (11 fins) 

 to Monopterygii (1 fin). Each class was divided, on the 

 basis of pelvic fin position, into such orders as Apodes, 

 Jugulares, Thoracici, Abdominales, and Achiri ( = 

 without hands, but with reference to pelvic rather than 

 pectoral fins, and thus would seem to be equivalent to 

 Apodes). The plectognath genera fell within the fol- 

 lowing classes and orders (Bloch and Schneider 

 1801:Lm-LVni): 



Classis VI: Hexapterygii [i.e., two dorsals, an anal, a 



caudal and two pectorals] 

 Ordo Apodes: Balistes, Rynchobdella [a mastacembe- 



lid] 

 Ordo Pinna Anali Carentes: Trachypterus, Gymne- 



trus [= Regalecus] 

 Classis VII: Pentapterygii [i.e., a dorsal, anal, caudal, 



and two pectorals] 

 Ordo Apodes: Ophidium, Pomatias, Gnathobolus, 



Muraena, Stromateus, Ammodytes, Sternoptyx, 



Anarrhichas, Channa, Sternarchus, Ostracion, 



Tetrodon, Orthagoriscus, Diodon, Syngnathus. 



This was the manner of listing in the index, but in the 

 text the Pentapterygii were placed in two orders (Bloch 

 and Schneider 1801:484-516), Apodes for the genera from 



