GENERAL AND STECIAL NAMES OF BONES. 49 



skeletal bones support the gills, and are in the form of 

 slender bony hoops, called " branchial^ arches." They are 

 articulated to and supported by the hyoidean arch. 

 Amongst the bones of the muco-dermal system, may be 

 noticed those that circumscribe the lower part of the orbit, 

 of which the anterior is pretty constant in the vertebrate 

 series, and is called "lachrymal," marked 20 in Cut 9. 

 In fishes, they are called " suborbitals," and are occasion- 

 ally present in great numbers, as e. g.^ in the tunny. A 

 similar series of bones sometimes overarches the temporal 

 fossge, and are called " supertemporals." 



At the outset of the study of Osteology, it is essential to 

 know well the numerous bones in the head of a fish, and 

 to fix in the memory their arrangement and names. The 

 latter, as we have seen, are of two kinds, as regards the 

 bones of the neuroskeleton ; the one kind is " general," 

 indicative of the relation of the skull-bones to the typical 

 segment, and which names they bear in common with the 

 same elements in the segments of the trunk; the other 

 kind is "special," and bestowed on account of the particular 

 development and shape of such elements, as they are modi- 

 fied in the head for particular functions. I would advise 

 any one earnestly desirous of comprehending this beau- 

 tiful department of Comparative Anatomy, to obtain a 

 prepared and partially disarticulated skull of a cod-fish 

 from Mr. Flower,^ in which every bone bears the initials 

 of its "general" name, and the numerals indicative of its 

 "special" name. A great proportion of the bones in the 

 head of a fish exist in a very similar state of connection 

 and arrangement in the heads of other vertebrata, up to 

 and including man himself. No method could be less | 



' Ante, p. 37. 



