508 MULLER ON THE STRUCTURE OF THE GANOIDS, 
genus Syngnathus. It will suffice to place the constancy of the 
valvular structure in all true osseous fishes beyond doubt, that 
types of thirty-five families of osseous fishes have been examined 
on that point, and that no deviation has ever been found. I 
have placed my observations with those of others in the sub- 
joined table. 
Osseous Fishes having two valves*, 
Order. Family. Genus. 
ACANTHOPTERI .«..... Percoidei (220. . 0. Uranoscopus, Trachinus*. 
Cataphracti......... Scorpena, Trigla*, 
Sparoidei....... »-»-.|Dentex*, 
Scizenoidei ......... Umbrina. 
Squamipennes...... Chezetodon. 
Scomberoidei ...... Scomber, Zeus, Xiphias*. 
Teenioidel ......... Trachypterus*, 
Teuthyes ............ Naseus*. 
Labyrinthici ...... Ophicephalus*. 
Mugiloidei ......... Mugil. 
Gobioidei............ Gobiesox*, Cyclopterus*, Echeneis*, 
Gobius. 
Blennioidei ......... Soarces*. 
Pediculati ......... Lophius. 
Fistulares. .........|Fistularia. 
ANACANTHINI uccoceess CFAAOIGELsoa0,, cbse one Gadus, Macrurus*. 
(PUIG sere sescsses Ophidium*. 
Pleuronectides ..,|Pleuronectes. 
Puaryncocnatui ...|Labroidei cycloidei/Scarus*. 
Labroidei ctenoidei| Pomacentrus*. 
Chromides ......... Chromis*. 
Scomberesoces_ .../Belone. 
PHYSOSTOMI...00sc0000. Siluroidei............ Calophysus*, Loricaria*, Hypostoma. 
Cyprinoidei ......... Cyprinus. 
Characini... ieseves Erythrinus*, 
Cyprinodontes...... Anableps*, 
SOCER waisvinene eases Esox. 
Mormyri ...... ++e..-| Mormyrops*, 
Salmones.......0+0. Salmo. 
Scopelini...... eee... /Saults* 
Clupeidz............ Arapaima*. 
Murenoidei_ ...,../Murzena. 
PLEcTOGNATHI ......|Balistini ........0.0. Balistes*. 
Ostraciones ...... .. Ostracion*. 
Gymnodontes ...... Tetrodon* 
LopHOBRANCHI ...... Lophobranchi...... Syngnathus*, 
* Tsolated and scattered observations exist in the writings of the older au- 
thors, as on the Salmon by Collins, the Swordfish by Bartholine, Walbaum, &c. 
The genus Gadus was examined by Cuvier; Uranoscopus, Scorpena, Um- 
brina, Chetodon, Scomber, Zeus, Mugil, Fistularia, Belone, Esox, Murena, 
Gobius, Hypostoma, Pleuronectes and Salmo by Tiedemann (Anatomie des 
Fischherzens), and Lophius by Meckel. The genera which I examined have 
a* affixed to them. As regards the orders in which the families are placed, 
I must refer to the development of the natural system of fish at the end of this 
treatise. 
