278 nsHES. 



postero-superlor angle to the side of the cranium, behind the orbit, 

 and by its anterior one to the anterior part of the cranium on the side 



portion, and has copied the figures which I had inserted both in the Annales du 

 Museum and in my Regne Animal. 



In No. in. of the same Journal is an arrangement of the bones of the head of 

 fishes by M. Bojanus, an academician of Petersburgh, accompanied by figures made 

 on the bream and the pike. 



The author difi'ers with me respecting the cranium only by giving a partial assent 

 to the notion of M. Oken, and makes my anterior frontal the cribriform lamina of the 

 ethmoid, and of the posterior or scaly temporal bone. He applies inversely, as I do, 

 the names of the petrous bone and the mastoidean. With respect to the external 

 occipital, he makes an interparietal bone of it, never remembering that it is always 

 outside the parietals. My suborbitals form his jugal, and he calls my jugal the 

 internal pterygoid, my temporcil is his chase, my chase is his external pterygoid 

 apophysis ; he regards the transverse and pterygoid bones as dismemberments of the 

 palatine. In fine he attempts still to discover the operciila in the pretended pieces 

 wanting in the lower jaw, an idea which M. Oken admires, and which is nevertheless 

 merely that of M. Blainville published five or six years before, and already refuted 

 two years ago by M. Geoffroy. 



M. Carus, the same year (l8I8), in his Zootomy, considers also that the cranium 

 is a union of three vertebrae, but he sees in the occipital vertebrae only four pieces, 

 forgetting the superior and external occipitals ; in the sphenoidal only five, never 

 thinking of the petrous bone ; my mastoideans appear to him to be temporeds, my 

 anterior frontal the cribriform lamina of the° ethmoid, my first suborbital the 

 lachrymal, the others the representatives of the jugal. He admits two or three 

 palatines, and calls my jugal os discoi'dien, and vaguely compares those which are 

 above the square bone, or the ascending branch of the inferior jaw ; in short, the 

 opercula appeared to him to have motion on the branchial apparatus, very nearly 

 resembling the scapula on the thorax, but he rejects the opinion which makes, of the 

 hyoid bone and the branchiostigal rays, a combination of the hyoid with parts of the 

 sternum, and with the sternal coats. 



In 1822 M. Bakker, in Osteographia Pisciun, has described the bones of the head 

 of the eaglefin and the lamprey. My posterior frontal appears to him to be the 

 petrous bone, as it receives no parts of the ear; my mastoidaen is his temporal ; he 

 takes my petrous bone for the great wing ; he calls my suborbitals the jugal bone 

 and the zygomatic bone. With respect to the bones which replace the square bone, 

 he confines himself to designate them by the names of symplecticum primum, 

 secundum, &c. 



M. Van der Hoeven, who has written in 1822, on the skeleton of the fishes, has 

 not ventured on determing the bones of the head. 



M. Meckel, in the second part of the second volume of his " Comparative Ana- 

 tomy," printed in 1824, has given page 2, 3, 4, and following a general description 

 of the bones of the head, with observations on their variations in some fishes. As 

 far as I can understand his text without the figures, and in which he does not put 

 everywhere the synonymes of other authors, his distribution only differs from mine 

 in his considering my great wing as the petrous bone, the orbitar wing as the great 

 one, and the anterior sphenoid as the orbitar wing ; insomuch, that he makes of my 

 anterior frontal an appendage to the ethmoid, and refers the posterior to the tem- 

 poral, and the preoperculum and jugal to the square bone, or to the articular portion 

 of the temporal, in fine : inasmuch as it is my suborbitars which appear to him to replace 

 the jugal, besides, he very well marks at what point it is necessary that the number 

 of pieces should be constant either in the cranium or the lateraJ apparatus. He 

 does not speak of the moveable pieces of the operculum. 



In fine, M. Geoffroy, in 1824 and 1825, made an arrangement of the bones of 

 the head of fishes, different from those of the opercula, with which he was much 

 earlier occupied, and in respect of which he maintains his opinion, that they are the 

 bones of the ear, he distributes the pieces of the head not into three or four ver- 

 tebrae like his predecessors, but he sees in and also admits in every other head 



